Man, I don't know about live window dragging:: do you have enough RAM? what's the problem?
Live window dragging is really really fast on my iMac rev.A/233 (96 MB RAM)..
Application launching used to suck, but since I opened more free disk space, it's much better. It still is slow.
Yeah, scrolling windows is not really bad considering it's live and it's Quartz content most of the time.
It has to do with GFX acceleration issues & VM management (which needs to be optimized a tad more). Also Desktop is too much of a memory hog, and dock, too.. did you check (in 'top') how much that thing spends?
What else to say than, write to:
BTW, there is a patch by Apple coming out soon, but this is still pretty unofficial.
However, I am sure it's mostly going to be bugfixes and stability improvements, it's still not time to remove debugging info.