In one of the more interesting acqusitions recently, online auction site eBay has purchased StumbleUpon, a quirky social search engine that recommends websites to users based on user preferences and previous ratings of their search recommendations.

I must confess that i’m not a big fan of the service, but it’s one of those offerings that require extensive usage to build you behavioral profile and like wine…hopefully gets better with age.

So why has the online auction site eBay ventured down this acquisition path?

“StumbleUpon is a great fit within our goal of pioneering new communities based on commerce and sustained by trust…StumbleUpon’s downloadable toolbar provides an engaging and unique experience to its users, but it is the similarities in our approaches to the concept of community that make it such a compelling addition to eBay.” said Michael Buhr (Senior Director – eBay) in a statement by the company.

According to the press release detailing the acquisition, StumbleUpon as grown 150% over the past year and “delivers approximately five million new recommendations a day to its large, highly engaged user base”. While the growth is impressive, the potential synergies between the two companies are still not obvious.

Maybe eBay is hoping to use StumbleUpon’s recommendation technology to suggest auction items to it users, but surely that technology wasn’t worth the US$75 million price tag. I’m sure we’ll see their plans unfold over the coming months.

Related posts:

• Movers and Shakers:: eBay wins the Auction for Shopping.com
• Yahoo! Closes Auctions as eBay Owns 94% of Market
• Bomb Squad and Firefighters Respond to Explosion at eBay Building
• Search Engine Technology:: The Three Kinds of Search
• Search Engine Technology:: Altering the Mindset