Yes, also, i think when the AI surrenders, all thier planets and resorses should now belong to whoever it was that they surrenderd to.  All thier ships and buildings including starbases should auto-distruct (planet up-grades should stay).  Is this not what surrending is?

When someone surrenders in online multiplayer, unless they're the last player on the team, the AI should keep playing for him as though he has merely quit.  That way people can surrender without completely dicking over their teammates.