Friday tabletop group, playing Warhammer:
There are four of us in this group, and we've all burned out on 3.0/3.5 (our last D&D campaign with this group was in 2005 and that was a very heavily house ruled, low magic, low powered group.) Me, my wife, and our GM are all sort of pro-4e, insofar as it seems to sound more interesting than 3rd Edition. The other player seems to have a quite negative impression of 4e, but I expect he'd give it a go if we decided to switch. That seems unlikely for this group though - there's a new Warhammer adventure path coming out around the same time as 4e and we'll probably try that instead.
Saturday OpenRPG group, playing 3.5:
We're playing 3.5 in this group primarily because our DM wanted to - previously I'd run an eighteen month long Iron Heroes campaign but that was my fourth straight long term campaign and I wanted a break. There are six of us in this group (me, my wife, and four players not in the Friday group) and we're all vaguely pro-4e. Our DM's said he'd consider converting his campaign if it wasn't too much trouble but as it's got quite a lot of house rules I expect it'll remain a 3.5 campaign. I want to run Dark Harbour (an IH module) for this group at some point, and my wife is working on converting her Iron Heroes setting to use the Warhammer rules, so we're fairly set for things to run for this group and if we run a long term 4th Ed campaign it won't be soon. We're likely to end up running a few 4th Edition one-offs though to test the new edition and give us a change of pace.