"One thing is certain, you can't criticize the Mint team for
lack of choice. With Linux Mint 12 you have the options of GNOME 3
with the Mint GNOME Shell Extensions (MGSE), GNOME 3 "classic," and
the GNOME 2.x fork MATE. Actually, I hesitate to call MATE a
"fork," given that it's simply picking up where the GNOME Project
stopped — it's really a continuation.
As the Linux Mint folks acknowledge, MATE isn't complete yet. If
you load up MATE, you get a pretty clunky looking GTK theme, and
some things just don't work right. If you're a hard-core GNOME 2.x
fan, this might be OK.