I've also the feeling that something is wrong with the registry compactor. Both with an earlier RC and now with the final version I noticed two things:
1. Directly after using the registry compactor, Windows 7 "liability history section" shows that "windows is closed incorrectly" (see attachment). This has something to do with the restart instruction at registry compacting, I guess.
2. I noticed no reduction of sizes of the different hives at all!
Some comment from anyone?
Rgds,
Herman