I'm usually not the kind of guy to play games online because I know how addicted I get to games, and I really, really want to have a life.
However, it seems that in 2012 Mechwarrior Online will go live. And I've always loved piloting a mech. I remember back in the day going to the Battletech Center in Chicago. Uff-da!
Anyhow, here's a link to the site. I guess it is F2P, and from an article on Ars Technica, they say that there will be items that you can buy with real world cash, but "any item that would give players a tactical advantage will have to be earned by playing the game."
Right now you can sign up to "reserve your pilot name". I was tempted to use my old Battletech Center call sign, Pavarotti, but opted for the white drew carey.
It also seems like they have tweaked some of the designs, as shown in the media page, specifically the Atlas, Jenner, and Hunchback. I've attached a comparison sheet to see the improvements (?).