There cannot be many heads of state who would devote a video blog to the virtues of badminton. Watch through to the end for footage of presidential badminton-playing, and see if you can spot the name-check of Yuri Gagarin at about 2:17 (which is an ad-lib, not in the published script).
PS - There is a theory going round the internets that Medvedev's opponent is Vladimir Putin, but I think it's too good to be true - you can't see his face clearly, and if it really was him I think you would be left in no doubt.
PS again - So much for my speculation. Kremlin sources confirm that it is indeed Putin.