Cinnamon is the Gnome 3 implementation of the same philosophy. I would put a bigger bet on Cinnamon, since the Gnome 3 infrastructure means it wont be going obsolete anytime soon.
Also, I'm confident that Mate won't be experiencing any major compatibility issues for several years from now, if ever. Along with Cinnamon, it's now the main desktop environment for the 3rd largest Linux distro, and the fastest growing one (Mint).
BTW, I like what I've seen of the Gnome3 SDK. It's just the interface that I hate. I don't understand why all the biggest distros (except for Mint) are moving toward exclusively offering a mobile-like OS for desktop. I could totally understand a special edition for netbooks, but Unity is now the only interface officialy available for Ubuntu. It all seems to be part of the dumbing-down of the desktop. Given that the biggest group of potential Linux users are Windows power users, who love being able to modify every little facet of their desktop OS, I just don't get it.