Morgano to get teh best possible speeds out of P7, do the folowing:

In Options there is a Render tab.  Set your processes to 4, despite your number of processors.  I only have one processor (single core et al), but there is still a speed improvement.  This is because P7 still takes advantage of ather little things in your computer (that I don't completely understand, but the results speak fo themselves.)

Also when you are doing a final render of a complex scene, choose the "render in separate process".

IMPORTANT (so many don't get this, ti seems):  Don't use "render in separate process" when trying to do a spot render or a very simple scene, in the one case you won't get anything but garbage, and int he other case you don't get any speed advantage because of the way it sets up before rendering.

BUT, if you are doing a complex scene, then you will have a marked improvement.

Yes, P7 will make use of higher end machines capabilities, specifically mutli threading and multi core processors.

Anyway, stability alone makes P7 worthy of an upgrade.  I am loving it so far.