I agree: "jerky" was my immediate reaction upon installing 4 beta 2. When you are so comfortable navigating with subtle mouse gestures, the halting quality of movement of the new version is unbearable. This is on a new, fairly high-powered machine.

However, I noticed one subtlety. When I would close 4 beta 2, reopen it, and zoom in quickly, it seemed to run smoothly for a few seconds -- 10 or 15 -- then the jerkiness would reassert itself. This suggests either some kind of memory leak, or some kind of memory buffer fills up and causes the jerkiness.

I had to reinstall GE 3. I couldn't stand to use the tool long enough to check out the new features.