I wonder if anybody can resolve a discussion I've been having elsewhere:
 
Would you say that the Team ICO games (Ico, Shadow of the Colossus, and The Last Guardian) are a series?  Do they all happen in the same narrative world?  Do characters span the games?  Will colossi exist in The Last Guardian?   Are they just three games that happen to be made by the same small studio?
 
Please comment your opinion - I didn't play Ico or SotC myself, but heard good things about them.