I've been playing 4th for a while now with my gaming group every other weekend. When I first looked at the books and read part of the PHB I was, like many, very skeptical. My first game session with the new 4E was a bit awkward, and we all were getting to know the very basic rules.
After the game session I thought "Hey, This isn't so bad." Two weeks went by and we got together again. After that session I was thinking " I didn't waste my money buying the new PHB. After several more sessions I am thoroughly enjoying the new version.
I will be converting the campaign I had going for my group in 3.5 to 4E starting them at 21st level. I am excited to see them take on the ancient black dragon and a few beholders!