For one thing, Georgia isn't exactly whiter-than-white itself (see
here - plus remember it was Georgian forces who started shelling South Ossetia*)
Plus Tibet's.... I don't know... more fashionable, I guess.
As to whose side I'm on... difficult to say. I'm certainly concerned by Russia's belligerence (not because I think it'll lead to WW3 - I don't - but because I find the idea of a nation with a man like Putin in charge being so powerful and practically unchecked quite disturbing. Say whatever you like about the USA, but they're a far, far more attractive alternative than anyone else on the table).
I think Russia has ludicrously over-reacted and deserves some kind of severe penalty or a message that such behavior is intolerable (which ain't gonna happen with Russia's position on the UN Security Council), but I think Georgia was very unwise to be so provocative. At the same time, however, it seems ludicrous that Russia was mediating the ceasefire between Georgia and the separatists in the first place.
*I'd like to note here that
I AM NOT EXCUSING RUSSIA'S ACTIONS - I'm as concerned as the next person. I'm just pointing this out.