I've been running Google Desktop (I've used both the regular and Enterprise versions) without issues on my Windows 7 64-bit PC for a long time with no issues. I just paved my PC and reinstalled Google Desktop (regular edition).
Initially, I want to use it only for the CTRL-CTRL launcher capability - I don't want it to do any indexing. So I unchecked all the items in the configuration dialog as well as excluded c:. Despite this, it is indexing all the content on my hard drive as well as Outlook email, etc. In my previous installations I had the same options set and they worked properly.
The other problem I have is that when you right-click on the Google Desktop system tray icon, there used to be an option for "Index Status" which showed you the percentage complete the index creation process was, as well as an option to clear and rebuild the index. Those are no longer there.
I uninstalled the regular edition and installed the Enterprise Edition, but same problems.