I use mostly the cinnamon fork of gnome-shell but I also give gnome-shell a try occasionally just to annoy myself :)
The gnome updates from Jan 1-2 caused me a bit of trouble, but I'm making progress that might help some of you: First, the addition of gstreamer-1.0 is now installed along side the old gstreamer-0.10, which apparently has broken rhythmbox. At first I thought that sound support was broken completely but after a few hours of frustration I found the breakage is confined to rhythmbox and a bug report is already filed. Second, when I use gnome in fallback mode, I found that the multiload panelapplet kept closing and refused to restart. I worked around that headache by turning off background transparency in the gnome panel settings menu. Third, the cinnamon clone of the gnome multiload panel applet was also broken, but the workaround is to update the applet from the 'Get new applets' link on the cinnamon panel settings menu. The new version is ignoring its own settings, but at least it works again. (The version you want is the one by Orcus, which replaces the older one by Ebbes.) I expect all of these bugs will be fixed when more gnome packages are updated by the gentoo devs. (BTW, I've switched to cinnamon because the upstream gnome devs are soon dropping support for the fallback compatibility mode.)
