^ I think the Heat's big 3 will stay put for now. But I wouldn't rule out a trade involving perhaps, Wade, assuming he is healthy. He is the kind of player a young up and coming team who can't seem to get over the hump and who has made a bad trade at the 2 position 8^), (cough-OKC-cough) could really use. Again, if he is healthy.
LeBron will get another chance to opt out in another year or two from what I've read. But he is boxed in between Miami and Cle. Imagine the outcry and vitriol if he moved to the Clippers or say, Golden State. I don't think he wants another firestorm at this point in his career.
I doubt seriously that the Spurs will return to the Finals next season barring some blockbuster acquisition. As great as they have been, one thing has shown for some time, this group does not play well after success (this last season notwithstanding).