I personally am not a fan of TF2. For shits, I decided to install it and give it a shot with a friend of mine. After logging in, I had literally DOZENS of hats and cosmetic shit just from all the other games and things I've purchased on steam or participated in. I did end up uninstalling the game merely hours after installing it, But it amazed me at how many I actually had. There were several that my friend told me were extremely rare, and it surprised him that I had them.
Unfortunately, Blizzard isn't partners with anyone to that caliber, but it would be really cool to get things like that. I had the Mt. Dew robot on a handful of my characters, and I don't even drink that stuff. But I had a lot of the fuel, too. I love little bonuses like that.
As far as how Blizz is going about it, if they release cosmetic items that are actually cool, I'd be all over it. I'm not a fan of the helms they released, and as such, have never bought them. In RIFT, once they released that store, fuck, I probably dropped $100+ just on cosmetic shit for my chars. I did not, however, buy ANY of the mounts or pets, because they aren't account wide like they are in WoW. If they were, I would've been all over them, too. I love stuff like that, and I don't care if it costs money, as long as the price is realistic.