CS4 is basically CS3 with the same bugs and idiocies, and a few new ones tossed in for sport. Heres a quick review on the parts i have toyed with so far today:
Photoshop:
Seems about the same. It might be the comuter, but it seems faster to load then CS3 out of the box. I'm not impressed, but i dont understand even 1/3 of what this program can do. Also it seems harder to use, but i attribute most of that to my now being used to GIMP. I have downloaded GIMP
Dreamweaver:
Its actually gotten worse. Ugh. I used to tolerate DW unless i was working on code, because somtimes the drag/drop and slight modify method was great for smaller projects. But its just....horrid now. And really unstable.
Flash:
I fucking love it. I have always liked Adobe Flash, and CS3 was really cool and easy to use. 4 is faster, and easier to navigate imo.
All i used so far