Linux Mint 13, codename "Maya" was just released last week. It is based on Ubuntu 12.04 LTS which means it will be supported until year 2017!
More info can be read here
Which regards to the comparison of it's interface, MATE and Cinnamon can be read here
For me I downloaded the Cinnamon version since last time I used "Mate" [I believe so].. at the end I decided to have both co-exist on my system. Seems I am so used to Mate.
If you already use Cinnamon and want to move to Mate, simply issue this command :
sudo apt-get install mint-meta-mate -y