Just a heads up really...
With the release of Modo 201, Luxology are also shipping ImageSynth. I have been playing with it since Wednesday. At the moment it is only available to Modo 201 users, but is planned to be released as independant PS Plugin filter.
If you have ever had an excellent small texture that you wanted bigger but didn't create those annoying repeating patterns then it may be just for you.
I have included an original 600x600 texture and then a 1200x1200 version after going through ImageSynth....please feel free to use them within your own work :)

Enjoy!

Cheers

The original texture

Post ImageSynth

As I see it, it makes the texture seamlessly tiled, right?

Thats correct Bruno.
This example is just a quick test...but there are various options to change, like itterations, how you want it to blend and even mix different textures together into one.

Cheers

It takes a little seamless texture map and creates a bigger seamless texture map from it while keeping the texture the original scale.  They patented this, so don't know if Photoshop will include it without having to license it.

Not to get too far off topic, but the German software program called "Texture Maker" (http://www.texturemaker.com/news.php) is excellent at making seamless textures, and at making a wild variety of textures from scratch. It is a stand-alone program for the PC. As for seamless textures, Texture Maker includes quite a few different processes for making a seamless texture from a small sample (or large) of something you already have. Some of the techniques included in this program will help you to avoid that "endless repetition" look. And the author does post trial versions, so you can check it out yourself. Me, I couldn't live without it.