A couple of things:
1.) I created a "Copied" version of a somewhat problematic Premiere CS4 project to another drive using Project Manager. The original project (standard def NTSC widescreen) had Panasonic P2 1080i media in it. Some of the media was from a Firestore which gave the clips long cryptic file names. This project was prone to crashing. I previously created a copied version that opened only once, then refused to open.
On the second try at creating a "Copied" Project, I went through all of the media in the the Premiere Bin before creating the copied project and shortened the long file name references there. This last version ot the Copied *.prproj opens and renders without crashing. So basically, I think the original Premiere stability problems have had something to do with excessively long file names.
2.) Also fo those of you using Windows 7 Release candidate, Maximum PC has an article that describes how to update your software to the retail version. I haven't tried it yet, but it may be worth a shot:
Nice tip on Win 7. Thanks.