Isn't steam community the facebook of gaming?
Steam doesn't even have the option to set a personal status, left alone something close to logging the previous status (stati?) or comment on what somebody else has done. Why can't I say nice job on unlocking achievement X? The "wall" really is a joke for that.
Steam goes into the direction, but it's still far, far off.
I don't think that will happen, the industry buzz is all about facebook integration, steam and b.net both have profiles with walls and stuff but they never get used in the same way.
While it might be easier to integrate with facebook, if you want to start monetizing you have to build your own stuff.
Let's throw a view into the far future: The gamer-facebook is so popular, every gamer is registered on it. Every big new game integrates into it, most even use it for their backend friendslist etc. Not using the gamer-facebook is considered a defect by gamers.
Now acti-blizz can charge for it. Maybe charge the users for premium features, or charge the game publisher for integration with the backend. No paying, no integration and no satisfied users.
You can't do that if you integrate yourself with facebook. Then only facebook can charge
you.