My guess is that Biden had better get used to it. In the wake of the Russian invasion of Georgia, Obama realized that, for politics' sake, he needed at least one member of the ticket with foreign policy credentials, and didn't want Hillary Clinton. (Without the Russian invasion, he might well have picked Tim Kaine.)
It seems that Obama genuinely likes Biden, but it would take a moron (and that, Obama definitely is not) not to realize that Biden is a one-man gaffe machine. Who can blame him for figuring that no one needs the distraction of another Biden foot-in-mouth moment?
With Hillary Clinton as secretary of state, the foreign policy rationale for Biden's presence is pretty much gone. And the evidence that Biden was picked for political, rather than substantive, reasons continues to mount.