The closest thing to a new 2D game is an amazing looking Simon's Quest hack with tons of new music, amazing graphics, more content/relics/bosses, being worked on by Optomon, Thaddeus, and some other guys (the only other one I've heard of is Silver X). It hasn't had a lot of recent updates but I've heard from Optomon that it's still in production.
Just as an example of a piece of its badassness, here's a new song in it (new to the game anyway).
Gears Go AwryNo new official games announced yet though.