The official Valve blog
has word that they have reached the 13 million user plateu. It's amazing how far the service has come since it was announced in 2002 as the service is now serving up 150 different games. I know there are people who still have a lot of problems with the service but I've been using it since Half-Life 2 came out and I've never really had a problem with it. I've used other online services (like EA's EA Link) and they still aren't as robust as Valve's service.