Social websites are shaping the future of the Internet as a social phenomenon. del.icio.us, Flickr, YouTube are some of the most successful websites belonging to the camp of Web 2.0. Sure, there are many other social websites and even more will appear in the future, yet StumbleUpon has made it. A long-rumored deal is a already a fact - StumbleUpon has officially joined eBay.

StumbleUpon, a popular California-based start-up, was founded in 2001. In March of this year,
StumbleUpon crossed the 2 million member mark and experiences a 150% annual growth.

It is interesting to see how StumbleUpon will be integrated into eBay. eBay has already acquired Skype and PayPal, both perfectly fitting into eBay's business strategy. However, in StumbleUpon's case the integration is not that clear. Though, a 2.5 million user community with a 150% annual growth rate is a perfect acquisition for eBay.