You'd think a government would announce something like that. And any change in the law would require an act of congress or the supreme court...I doubt Uncle Sam is ever going to be happy about Bitcoin unless they can control it. Will we see a fork for UncleSamCoins? I doubt that too. Is Uncle Sam gonna allow banks to hold Bitcoin as currency for meeting reserve requirements? I doubt it.
But now I really am curious...
UncleSamCoins is never going to happen unless it is something like MintChip, but that's centralized. There will never be a P2P UncleSamCoins or MintChip. I've said it before, and I'll say it again, the blockchain and the basic rules and operation of the protocol are not going anywhere. There is now over $100 million in the blockchain and protocol. Any major rule changes from Gavin & Co. on Bitcoin.org will probably result in an almost instant forking and mass defection to another client with the current blockchain. It would surely cause chaos initially and would probably cause a big price drop, but it would happen.