I'm using GNOME 3 on openSUSE 11.4 and everything is (almost) fine. But something that I missed was the taskbar, but no more, thanks to tint2.
tint2 "is a simple panel/taskbar unintrusive and light (memory / cpu / aestetic)".
Unfortunately tint2 isn't available through Yast, so we have to do this in a hard mode (not so hard).
Grab the source code from http://code.google.com/p/tint2/, unpack and enter into its directory. Open the INSTALL file and you'll see that is very simple to build tint2. You just need to create a directory and execute cmake, make and make install commands.
At the end, you'll want it to execute automatically. The easiest way is through gnome-session-properties tool. Add a new entry there and do logout/login.
And you also get, completly free, tint2conf used to manage your panel themes.
