MATE and Cinnamon are two recent additions to the list of desktop environments and window managers available for Linux and BSD distributions. You see, in the free software/open source community, there is nothing like too many options. The more, it appears, the better.
The aim of this article is not to present a point-by-point comparison of the two desktop environments, but to present a general overview, so a new user has a top-level idea of what they are.
MATE is a fork of GNOME 2, started as a result of widespread dissatisfaction with GNOME 3. Cinnamon also arose out of widespread dissatisfaction with the default GNOME 3 interface, but unlike MATE, it is atop the GNOME 3 code-base. In effect, it is the same GNOME technology, but with an interface that is just like that of GNOME 2, or the type of desktop environment that we are used to. Another way to put that, is that MATE is old technology, while Cinnamon is new technology.
While I do not particularly like the default GNOME 3 interface, it is a major improvement over GNOME 2 and, therefore, over MATE. Both are works in progress and have a similar desktop layout. They are what most people expected GNOME 3 to be. Rather than presenting users with a new and, to some, an unsuitable-for-desktop computing interface, MATE and Cinnamon offer a familiar environment to many. Whether that environment is better than the new one depends on the individual and what he/she is comfortable with.
If you have not used with MATE or Cinnamon, the best way to decide if they are worth using, is to evaluate them yourself. That means downloading Live images and running them on your computer – without installing them, of course. The distribution that makes it easy to do that is Linux Mint.
The most recent release of that distribution made Live environments of a MATE and a Cinnamon edition available for download. You can get both here.
Meanwhile, the following screen shots provide an idea of what the desktops looks like.