So I use Ubuntu 12.04 on my laptop and Linux Mint Debian Edition on the desktop. LMDE is OK, but I'm not sure Mate is a long-term solution. On the one hand it is great that they have maintained the old look and feel of Gnome 2, but forking so much "crap" seems like a huge wasted effort.
For example the configuration changes - instead of gconf, you now have mateconf, which uses a whole other set of files that are not compatible with gnome. So switching from an old Gnome desktop (say) to Mint+Mate means your settings are all lost, even though the forked code between gnome2 and mate is really close.
On a default LMDE install it adds gnome-terminal and mate-terminal, so on the menus you have 2 "Terminal" entries. Ditto for a load of other core applications that are in Gnome and Mate - stuff like Archive Manager, screenshot, and document viewer. Was there really a need to fork file-roller?
Debian have already pretty much said "no" to including Mate - the reason being that the duplication and resuscitation of crufty old code is not a good idea. It would be better, the say, to work with Gnome upstream to get a more Gnome2-ish feel in Gnome3. I think Cinnamon is in Debian or will be shortly, which probably has a brighter future.
Anyway, for now I'm happy with Mate - it works fine and didn't need any tweaking to get to a usable state, compare that to Gnome3 classic-session on Ubuntu 12.04 which I spent weeks tweaking and patching (!) to get back to a state that worked like 10.04 - but I think its days are numbered. The Mint devs alone can't keep a full-on Gnome2-fork alive forever, it has too many duplicated applications that are already fine in base Gnome, and eventually I think Cinnamon will be the only viable option for Mint.