News that President Obama has taken to singing in public reminds me that it can be a seriously damaging pastime for political leaders - as James Callaghan found out in the aftermath of his rendition of Marie Lloyd's Waiting at the Church before the 1979 general election (HERE)
My impression from the above is that the president would be well-advised to concentrate on his public speaking and to avoid any more temptations to sing in public.
It may show what a jolly good sport he is to join in the fun. But even as dubious a character as President-to-be Putin can do that - and, on this evidence, has a rather better singing voice (or has spent more time rehearsing) than President Obama:
Or maybe Putin's just miming...?