A lot of good posts on here with some very good points.
I had a 42'' PX80 spent ages in the shops comparing against the 1080p Z80. I could see the difference, when I knew I was looking at a 1080p and standing about 2ft away.
The thing is I sit 7ft+ away from it, so saved 200 and got the PX80.
I now have a 42'' V20, was never happy with the PX80, it wasnt the res though, it just didnt have the deep blacks I expected and seemed flat compared to the G10 when it came out. Ther is more detail on my V20(playing blurays) Avatar has more detail on my new set its undeniable. The most impressive thing is the contrast though, no point in having 1080p if contrast is crp, its contrast that gives depth and the pop IMO, the extra shadow detail isnt down to 1080p ether. 1080p is an improvement for 1080p material on my new set, but!, if it wasnt for the other more important (IMO) improvements like greyscal, gamma, colour gamut, contrast I doubt it would be noticeable just as it wast on the z80.
As many have said their is no point in having 1080p if your not going to be watching 1080p material. And sorry but 'no', most Xbox games do not run in 1080p(the amount of game forums going about who has the most 1080p games cracks me up lol), they can be upscaled to 1080p, thats not better, its upscaled lol. Same goes for PS3, its hard to make a game with high polly counts and decent physics run at a decent frame rate, trying to get over 30 fps at 720p on console is tricky let alone 1080p.
Only point in having a 1080p 32'' set or smaller is fo pc use, you just wont notice the difference on anything else (unless you sit the same distance for 1080p films I guess lol) its just marketing bull IMO at that size for most.
Personally at below 50'' other things are way more important IMO.