At one point the Sharks franchise was almost awarded to Seattle. It took a lot of last minute dealing for San Jose to secure the deal. I believe it included their promise to build the "Shark Tank" which is a hockey specific arena (although they do play arena football there, it was designed for the Sharks for hockey), and not try to play in another arena somewhere not in San Jose. I like that arena they have because it's right in the historic San Jose downtown and easy to access.
I think the arena in Seattle is going to be awesome, and once its done, the whole area is going to just become sports junkie heaven between the 3 stadiums along the SoDo area. Hopefully it picks up that part of town with more shops and fun pre-game stuff to do, rather than just a bunch of scary warehouses where you pay to park and hope like crazy your car is still there when you get back. Eeek!