Wow. Turn your back on eye candy for a few weeks, and it just jumps up at you.
First, the new SLED menu for GNOME developed by Novell was dropped into GNOME CVS as 'slab'. Of course, people have customized it for their favourite distribution, and so now there are Fedora and Ubuntu packages of it available. Keep an eye on the plan to get the slab into Edgy Eft.
A lady by the name of QuinnStorm has done some amazing work with Novell's XGL and Compiz, really building a community around it. I track the development version of compiz, which just keeps picking up new and useful features - I don't really like the Expose-like funtionality, so I went to see how to turn it off, and fell over a new window decorator instead. Cool. (If you have the bug that you can't seem to turn off hot corners, read the compiz.net forum on the issue.)
A great list of things to configure about Compiz can be found on the Ubuntu wiki. Someone wrote a program called gset-compiz to do this all for you, but development hasn't kept up with the rapid pace of Compiz changes. (Hint: to stop background windows appearing faded out, disable the "trailfocus" plugin, and try hitting Ctrl-Windows or Shift-F9 if you have "water" in your list of enabled plugins!)
It also turns out that the aforementioned slab is available from QuinnStorm's repository. Is there anything she doesn't do? The only criticism I've seen is that the domain could be slightly more trustworthy-sounding than "beer or kid". Tough choice, even for someone who doesn't drink beer...