I'm 60 hours into my render and still going. I have a quad core, 64 bit system. The image is filled with imported objects, with at least two really large texture maps, a few smaller ones and procedurals with displacements. The image is large (1155 times 1200) with a radiosity atmosphere, two additional lights and several ecosystems. Render is set to highest quality level on the pre-configured list.  (I should mention I'm using Vue 6 Infinite, last build.)

Is the time this is taking unusual, or is it just something that people experience when they get ambitious with their scenes? 

Well I had a render that took 8 days to run when using Vue 4.  Move forward to Vue 6 and the longest were set going overnight and finished when I got home from work so 12-16 hours.  So far with Vue 7 my longest render was 2 and a bit hours. 

The only preset render settings I use are OpenGL, Preview and Final.  Everything else I go to user settings.  I normally try rendering very small version with user settings before doing a final render.  Then tweak the settings and incrementally increase the image size.  Normally I save a lot more time than it takes to optimize my settings when I do the final big render. 

With those settings and content you mentioned, the 60 hours are not surprising to me. My longest render ever was about 24 or 25 hours, if I remember correctly, my average render is 2 or 3 hours. If you look at my gallery, you'll see that most of my images are fairly complex. I also use a lot of radiosity. For example, my latest image was rendered in radiosity, it has several ecosystems, billions of polygons, reflections and transparency, procedural terrains, and it rendered in 3 hours. And I think it looks very realistic, but you can judge by yourself.

First of all, I would say that you shouldn't use the pre-configured list of render settings. Those presets are very poorly balanced, in terms of AA and advanced effects, for example. You are wasting render time for no visible increase in image quality, most of the times. IMO, you should use user-settings. Peggy Walters has an excellent tutorial with very good practical advices for this (I don't have the link at hand, maybe someone else reading this thread will).

The "secret" to my 3 hours rendering time is render and atmosphere settings adjusted to the minimum setting that provide good quality. I don't put any slider even a bit to the right if it's not needed. To know if something is needed or not you should experiment. This experimentation is made very easy with that excellent document from Peggy.

One simple trick that some people neglect is the quality boost in the light tab of the atmospheric settings. In most cases, you can put that in highly negative values (like -1 or -2) without any noticeable impact in quality. The impact in render times is tremendous. Another thing is "advanced effects quality". In most cases you can use 40% or less with no visible impact in quality. Etc, etc. It's all in that precious document. :-)

Just to add:
For example, if you look at Ultra render settings, you'll see it's very poorly balanced. It has very high advanced effects quality and too low AA (specially if you are handling plants). So, what's the point in having very good volumetrics and procedural and displacements (as granted by the high advanced effects quality) if you have very poor AA? That's why I say those settings are no good. Those settings are too generic to be any good.

http://www.sharecg.com/v/23774/tutorial/Vue-6-Infinite-Render-Settings

Now I need to update this for Vue 7... 

509 hours for me.

70 hours, using my "super dooper fine detail settings with a glacial render time!*
turned out it was because of the metacloud I'd used for fog, having it enclose the scene ramped the time WAY up, without it, it was only 7 hours to render (on my  quad core, with Vue7)

I designed these settings  for Vue6, maybe for Vue 7 I can switch it back to Optimized AntiAliasing?

yes, they this is a VERY slooooooow render setting, but it does enhance detials, I preffer it :)

Silverblade, if you're aiming at "detail enhancing", I would say that texture AA will probably do the opposite. That's what's written in the manual and it's my experience too. Here's what the manual says about texture AA:
"While the results produced using some amount of filtering are generally smoother, you may
occasionally find that your images are not as crisp as you would like them to be."

Personally, I only use texture AA when I see Moire patterns.

Another important thing is the quality threshold in object AA. I would say your setting is ok for characters and nomal objects but it's too low for plants in the distance, like grass or similar. It's also too low for some kinds of spectral clouds (grain is likely to appear). Whenever I have clouds or plants, I normally use quality very close to 100% (exact amount depending on specific types of plants and clouds). If I have just a normal interior setting, no plants, no clouds, 50% is normally enough.
If you have quality AA at 100% or close, it's pointless to have min subrays very high because the render engine itself will evaluate what's necessary. I normally have it with 8 or so.

The "compute physically accurate caustics" will effectively slow render tremendously and if you just have an ocean in the distance, for example, it will not be noticeable at all. IMO, this setting should be set only when whatever's behind the water level is clearly visible to the viewer. Or if you have glass stuff in close-ups.

I let my machine render for 2 weeks once.

I can't remember which picture I was working on because I swore I would not do such a long render ever again.

I start drumming my fingers after 10 minutes   

Seriously though, I've had the odd overnight renders but most times I never set the quality up high as I'm addicted to postwork.  My 'average' is usually between 2 and 6 hours.  The odd few have been less, especially in scenes where I needed nothing special and got away with the old standard atmosphere.

When I was a beginner I allowed rendertimes up to 72 hours; now I want to awoid that madness for a single pic so nowadays I render "overnight" (10-12 hours) otherwise I have to edit the render settings...no way I would render a single image for 60 hours on a quad...unless somebody PAYS for that! :-)

My longest was about 180 hours for a 1000x800 (ish) pixel sort of image. Was playing around with trying to get smooth soft shadows out of vue in an interior scene and got a little carried away with AA.

I started a render last night of a high resolution scene with one of the new procedural water planes resized so it went well over the horizon, spectral 2 sky and a reflective/transparent material on the water.  User settings I'd tuned a bit first.  I thought would take 6-8 hours and Vue 7 did it in under 2...

7 days, nearly all devoted to rendering some pretty complex water. When finished -rendering to screen- I went to save the image and Vue 5 crashed. Brought tears to my eyes!
Won't do that again.

Longest render for me was over 3 weeks on 5 render cows, non stop, no crashes.

Multiple days were common in the old versions to get good lighting and atmosphere.

In 6 Infinite, I just had one go about 60 hours with just a sky, clouds and water. I was testing a new sky with some new clouds I'd worked up and a new water material. I wanted to once and for all see what Vue would do, so I set all the sliders to ridiculous.

The sky came out awesome with the graininess gone and the most realistic clouds I've managed but the price in time was high. I would not do it except to print a still as a poster.

Ah I found out why that took so long to render: I had used a metacoud to create fog, that was the culprit for some reason!

 My longest is something like 48 hours, but that was an insanely complicated piece.  I've found Vue 7 takes SOOOOOO much longer that Vue 6, though - I'm doing a comparison render - exactly the same image (though with a couple of tweaks - I'm using the new Vue 7 clouds and dynamic population for the eco-system).  The Vue 6 (infinite) took 7 mins to render at 640x480, set to final.  Same settings for the vue 7 render, but so for it's 40% done and has been going for about 4 HOURS.

Anyone got any idea how to reduce the render times for Vue 7?  Having both 6+7 installed on the same computer might not be helping, though....

If you use dynamic population, the render times cannot be compared. With dynamic population, Vue7 populates while it renders, Vue6 populates before rendering. Furthermore, if you are using the new spectral 2 clouds, again you cannot compare with Vue6 because the new clouds are more complex than those of Vue6. I find Vue 7 renders faster than Vue 6, in my average scenes.

For some hints on render, see this thread:

http://www.renderosity.com/mod/forumpro/showthread.php?message_id=3357632

There's no technical problem in having Vue 6 and 7 installed on the same computer, or even running them at the same time, provided you have memory for both (I'm not sure about the legal aspects, though... if you bought Vue7 as an upgrade to Vue6, legally I think you can not run Vue6 anymore).

 I see...thanks, Rutra!  It ended up crashing on me anyway - I'll try re-loading the scene and rendering again with the exact same setting to compare render times instead.  As for Vue 6 - I was going to get rid of it anyway.  I purchased Vue 7 Complete as a sidegrade from Vue 6 Infinite - I only had Vue 6 on my computer until I worked out if Vue 7 would work properly (for some reason I couldn't download the Pioneer version to try it out).  Now I know it;s all A-OK and working, I'm going to get rid of 6.  Thanks for the pointer to thread, I'll have a thorough read of that.

it appears the timer in complete may have some bugs....

 Yowza!  I've not had that issue yet.....