StumbleUpon gets one billion 'stumbles' a month

"In January, we reported that StumbleUpon had broken a new record with 27.5 million stumbles in one day. At the beginning of this month, we interviewed Marc Leibowitz, StumbleUpon’s VP of Marketing and Business Development who told us that since 2009, StumbleUpon has grown from 6 million to 15 million users. Recommendations have tripled, now surpassing 800 million every month. Each month, over 3-4 million users are active on StumbleUpon, with the primary base being in the US.
Today, they’ve just crossed a new threshold: 1 billion stumbles per month.  StumbleUpon is now driving billions of visitors to websites that have been “Stumbled.”"

Source:  TheNextWeb, 6th April 2011