First and foremost, the relationship of Superboy and Miss Martian is dissolved... Miss Martian apparently left Superboy for Lagoon Boy over the time skip, but Superboy doesn't seem to be over Miss Martian. Returning from the Clayface mission, she runs up and kisses Lagoon Boy and Connor was annoyed by it.
Zatanna and Rocket ARE graduated into the League...
first few minutes and mind is already going a mile a minute! discuss discuss discuss!!!
edit: Nightwing, Miss Martian, and Superboy are NOT in the league, but Zatanna mentions that membership is open to them.