API wise there isn't any difference (at the moment), so you can simply swap out the Maven dependency for whatever version works best for you. What time brings, we'll only see...
Actually Scott has been maintaining Morphia pretty actively until he has been hired by 10gen. I'd assume MongoDB is too successful and they are drowning in consulting work (no inside information, I'm just guessing).
So hiring is no guarantee for active support (even though I've had the same hope)...
Cheers,
Philipp