Microsoft said Friday it has reached a deal to acquire Greenfield Online, the owner of consumer shopping sites, for about $486 million. Greenfield's properties include Munich, Germany-based Ciao, one of the leading price-comparison and online-shopping sites in Europe. Ultimately, Microsoft said, Ciao's technology platform, online community, and merchant relationships will be integrated with Microsoft's Live Search.

Ciao features consumer reviews and ratings. Microsoft said that, according to ComScore, Ciao has more than 26.5 million unique visitors per month across seven countries, who have generated more than 5 million product reviews. The deal calls for Microsoft to commence a cash tender offer to purchase all of the outstanding shares of Greenfield for $17.50 per share, or roughly $486 million.