Martin Wimpress posted on Google+ a picture of an early MATE version of Ubuntu along with the comment, "There's something cooking and it smells delicious. Thanks to +Alan Pope for the help." In a follow-up comment he explained, "Who knows where this will lead. But it would be cool if we can pull it off [an official Ubuntu version of MATE] :-)" He also added, "it is all Ubuntu but the screenshot I posted is a big dirty hack on top of a prototype that is less than 24 hours in the making."
For what it's worth, embedded below is a screenshot of this early Ubuntu MATE prototype. We'll see in the days and weeks ahead if an Ubuntu MATE spin will actually start brewing for the 14.10 Utopic Unicorn cycle.
The latest MATE release is MATE 1.8 and it made its debut in March. MATE can be installed upon existing Ubuntu/Debian installations right now and the desktop is also available for installation from Arch, Fedora, Gentoo, Linux Mint, Sabayon, openSUSE, and other Linux distributions.