I took the plunge and upgraded to WordPress v2.5 today. It only took me about 1/2 hour and it went pretty smooth. I used the Automatic WordPress Upgraded plugin. It worked well until it got to the point where it needed to reactivate all the plugins. It asked me to login again and then asked if I was sure I wanted to do this. I said yes but nothing happened and I had to reactive my plugins manually. The backend to v2.5 is totally different so it took me a minute to find my way around. Everything seams to be working.
Now I just have to figure out how to enable the new built in gallery.