I've never seen numbers on users vs. number of games played, but an anecdote: I and many of my friends are pretty heavy Facebook users but few of us play many,

I've never seen numbers on users vs. number of games played, but an anecdote: I and many of my friends are pretty heavy Facebook users but few of us play many, if any, games... just status updates, photos, and messages. But I also have a few friends that seem to play 50 games for every status update they post. I wonder if there are two groups of Facebook users, one that mostly chats and one that mostly plays. That's how I tend to think of it at least. So if I were trying to make a Facebook killer, I might attack one of those two groups... provide either a vastly better social/chat/discussion/link-sharing scheme or a vastly better scheme to play games. But I don't have any ideas on either -- they both work pretty well apparently (the completely technophobic all have Facebook pages at this point!), which makes me think it'll be really tough to compete with Facebook. And, besides, if you did compete that way, you'd still be at a disadvantage because of the network effect and that you appeal to only a subset of the existing Facebook crowd -- as I said, I don't play a lot of games, but I still want to be friends with people I remember from high school and that do.