I saw this too... just to note, the service is an add-on, NOT REQUIRED for multiplayer online game play. I saw the service in beta, and though I haven't really played MW, my take is it is a community thing... similar to what BF3 did with the website game launch thing.
My personal guess on this is, 2 years ago when most of these game were in design, gaming consoles were pretty much accepted as the gaming system of the future. That is PC gaming was accepted as dying and going away. I think these systems are to bring to PC gaming what is built into the console world. I think MW's service is to allow the PC people to "enjoy" the same experience the console people have. Which to me is a negative... but whatever, they are going to charge for that "experience" not for the online gaming functionality.
As for BF3, I think they realized their mistake in time and changed to make more of a facebook online community... and not charge for it... but instead take in ad revenue.
Either way, the nice thing in here is console sales are dropping and PC gaming is growing... and the numbers are pretty impressive.
So, for now, we are saved. Could just be the consoles are getting dated. We shall see.