Ok, let's start a list and then I'll poll it! Remember, this is not really about MMOG but about making the engine more MP friendly which in turn will make it easier to make a MMOG (which is still the hardest thing in game development... nothing the engine can do or offer will change that fact)

- Lose DPLAY and go with Raknet, Enet, ???
- Server to server communication
- Lobby system
- Security Fixes (ie: the ability of a dummy GS client to crash ANY GS server)
- File transfer
- Web Player
- Individual Client update
- Better network diagnostic panel
- Native MySQL integration

Anything else, please build on this.

(PS: Stupid question but I'm not seeing the obvious way to create a poll as a new topic)