I've been using the MSN Desktop Search (I'll refer to it as that since I have no use for the rest of the toolbar suite and immediately turned it off) for the past few days and it is good enough to make me uninstall Google Desktop Search.  The fact that it, by default, indexes source code, xml and anything I can write an IFilter for was enough for me.  I also like the search as you type.  Very well done.

The only problem I have is it seems to conflict with WindowBlinds, software that lets me load thousands of visual themes for windows.  I have to unload WindowBlinds, search for something, and load it back up again.  Then everything works fine.  I suspect it has to do with the order that applications register hooks (which has caused problems like this before).