U must really think that they will no get extra tearing with compiz, but most likely they will introduce just that if not already happening. They should take a look at xbmc i would say... Usually xbmc runs best fullscreen effects disabled. Btw. xbmc mainline was merged with opdenkamp's pvr branch recently. So the main repo that's not merged is just FernetMenta with xvba support. FernetMenta was usually on top of opdenkamp and now on top of mainline - so i hope xvba support has got higher changes now to get merged.
All that in less than 2 years. It's always more fun starting new things, than maintaining and refining the old stuff.
They've dropped a mature and flexible lib like Qt, in favor of their own in-house GUI toolkit based on the buggy Compiz (Not-Invented-Here syndrome)
They've started a lot of projects and left everything half-done:
-Global menu/HUD: doesn't work reliably and not in all applications, a lot of hacks and workarounds
-Dash/lenses: slow, buggy, only bearable using search(when it works) navigation is atrocious
-Compiz/Nux: unstable, only works with 3D accel, a LOT of new and old bugs
-Ubuntu Software Center: slow, slow, slow
Will they squander the donation money writing and rewriting this garbage?
The polish that gave Ubuntu popularity is nowhere to be found.