Photoshop 7.0 is quite stable at this point. It has not crashed on me yet. As of beta 43 the app is a bit slow though, but on a G4, well, then nothing is slow...
What suprised me the most about this beta, is that all important functions of the app seems to be there already. Color correction, layers, levels, paths, curves, variations, masks, filters. And of course, the aqua interface. Quite nice (but Adobe should add an option to turn off drop shadow on the toolbars...). The new file browser is also quite handy. Much better than the open file dialog.
What really makes this a beta, and not a retail version are mainly three things: Speed, few added features (as of now, it's pretty much a carbonized 6.0 version, with a couple of new features), and the butt ugly icon...
Adobe is doing a great job with this app. IT IS going to rock!
PS! Just ask if you want some screen shots. I guess I'll find your e-mail address in your profile?