I think the value of Cinnamon per se will soon far outstrip the value of maintaining a separate distro altogether. It may make more sense to leverage all the core libraries of Ubuntu and roll Cinnamon (and the best features of Mint) into a easy to install desktop.
If we analyze the recent upsurge of interest in Mint, it is primarily driven by hate for Unity than any other aspect of Ubuntu. As far as other multimedia and software packages are concerned, a "cinnamon-desktop-clean" top level package for Ubuntu baseline can do eliminate all unnecessary packages and install Cinnamon + relevant features of Mint.
Cinnamon has the potential to be one of the three desktops - Unity, Gnome 3 and KDE being the current top 3.
Does the rest of the community think that Linux Mint will be less important/valuable than a cinnamon-based desktop focussed towards seamless integration with Ubuntu baseline ?