ZeroZero
If you want to play I would say that my system is pretty good. It has been reliable enough for some time that I now have it on three machines.
In your spare partition ....
Install LMDE Xfce Edition and update it and add your video driver. When is is set up and running activate sid and experimental in your sources.list, update but do not do an upgrade.
http://forums.debian.net/viewtopic.php?f=6&t=60481sudo apt-get install -t experimental gnome-session gnome-themes-standard gnome-control-center gnome-keyring gnome-media libdconf0 dconf-tools gsettings-desktop-schemas
Then open Synaptic and search on Gnome and gtk and add anything that looks like it is for Gnome3 - version 3.0.x is a dead give away. It is a slow tedious process. Add Tweak Tool as it is vital, also gnome-common if you want to compile anything.
Restart and log into Gnome and you should have a running Gnome-Shell. Once you are happy edit sources.list and comment out sid and experimental and do an sudo apt-get clean, then do an update and always use this command for updates
sudo apt-get update && sudo apt-get dist-upgrade.
I also added a few bits from KDE to cover some missing bits. Add Dolphin and kde-filesharing, plus K3b and Amarok.
Once my systems were stable I went in and removed Xfce, but that is unnecessary and it is handy to have as a backup if things go pear shaped. Gnome fallback is also available in the menus at the login screen.
Then add extensions in ~/.local/share/gnome-shell/extensions just like in Fedora
If anyone else has a better or simpler way then speak up. That is how I approached it and it does the job until there is a real Mint Debain Gnome-Shell.