A long tail story...

Interesting graph from O'Reilly research showing users of the top50 apps in Facebook (that's the top 1% of the 5,000 Facebook apps).
Behind the Slide miracle with its millions of users, only 44 other applications are getting more than 100,000 users, out of the 41M active monthly Unique Users.
Interesting reality check isn't it? Definitely considering a Facebook app should be part of marketing mix but be careful to not bet the farm only on it...