though, having one system to tell you when someone starts playing a game on any system is kinda neat. To do that now, you need the PS3 site, 360 site and Steam opened up. And still that doesn't cover some PC games.
I like the cut of your jib. It would be even better if there were a service where you could be immediately notified if a Friend started playing a multiplayer-capable game which you also own.
But before that, I'm still wondering why MS hasn't put in the "Which of my friends owns this game I'm playing?" search function.
It already does that "Friends playing this game" notification, which is neat, but why not also support a query such as "
this friend also has Achievements in
these games you own," or "
these friends also have Achievements in
this game"?