Yes, it's possible if you enable the sid repos. With sid you can update your gnome packages to Gnome 3.0.
If you enable the experimental repos you can update to Gnome 3.2.
All around it is discussed here:viewtopic.php?f=201&t=65745&start=500
I believe in everything, except humans.
LM9, Debian Testing Xfce, Debian Sid Xfce - CPU/Amd64 2,6Ghz, Graphics/Nvidia 9600 GT, Sound/SB Audigy4 emu10K1