Rumours starting to link Mark Schwarzer with a move to Arsenal on a free - could be a good move for us. I think Mannone will leave this summer, maybe Fabianski too, but you don't get much more experienced than Schwarzer, and Szczesny would benefit from this alot, I think.
I don't think we need a new long-term goalkeeper anyway, Mignolet and Julio Cesar are top-class, but Szczesny is also a top player, who has just had a poor season - it's worth mentioning that Cesar also had a poor 11/12 season for Inter, that led to his departure.