Rated 5 out of 5 stars
I love Greasemonkey! It continues to work perfectly well with FF4 RC under the default Theme. So, this isn't a Greasemonkey bug, but I've noticed a problem under some other Themes, for instance Office Black which I just installed.
In my Tools/Add-ons screen, with the default theme I get to see Userscripts (Greasemonkey) in the same left column with Extensions, then am able to open a userscripts screen to fiddle. With Office Black, Userscripts is invisible. I've seen this problem with a couple of other themes.