Just received my universal FCS today. Am just a lowly film student, and as such wouldn't call myself a pro, but I do a lot of editing, and I'm doing it on a 20" 2GB intel Imac (which is not only practical with my budget, but also plenty fast enough for all but the most intensive Motion use). The universal crossgrade is currently working ok, but just ok, it certainly renders faster than on the G5 (I managed to trade my 20" G5 for the intel imac in Jan with a bit of luck on my side). The problem thus far is still a codec issue. An in-progress project which I transferred from the G5 works for the most part, but there are certain .avi files which simply crash either FCP or DVD Studio whenever I attempt to open them, and mpg files play without sound in FCP (I'm not sure if this was always the case, to my memory it wasn't).
Also, just for laughs I used to import .avi movie or tv show files and toy with them, recutting and redubbing dialogue etc...this isn't something that was ever done with any degree of seriousness...but now the large .avi files crash it again.
Now I realise this is a codec issue, but it is still a little bit irritating.What is good to know though, is that on flat out performance, there is a definite improvement, and as the majority of people using the software will be transferring straight from their camera's to FCP, there shouldn't be any major issues.
And just to add my two cents, (or pence I should say) whilst it still obviously isn't professional standard, the imac has suprised me at how adequate it is for DV editing. I haven't tried it with HD, but for a prosumer it not only looks the part but is actually pretty decent.