Here on the forum doesn't matter either. The people who post here are more likely to be PC gamers by virtue of the fact that they are, for the most part, posting from PCs. An overwhelmingly vast majority of consumers of the TES franchise do not ever come here to discuss anything at all. If you honestly think PC gamers aren't in the minority then quite frankly you're deluded. I shouldn't even have to point to the fact that the game is being developed for the Xbox 360 and ported to PC.
I just googled for a good while, trying to find accurate total sales for Oblivion, Xbox vs PC. I couldn't even find an accurate sale-to-date since 2006. There is no argument here. I must be deluded by the huge amount of "PC" fans on the forum - the forum is the only real judge I have of who's who in the scheme of things.
The people who post here don't necessarily need to be PC gamers, they simply need a PC to post on they're game's community forum. Still, the vast majority of the system-specific posts and topics I see seem to be concerning the PC (and despite this, they're usually a loud group saying "save the PC, we're a minority!")