Earlier this week rumors began emerging that travel pricing, comparison, and booking site, Farecast, was the takeover target of a mystery buyer. Well, it turns out the mystery buyer is Microsoft, with the company today confirming the acquisition and reportedly coughing up $115 million for the Seattle-based startup.

Farecast competes with similar web services like Travelocity, Orbitz, and Kayak, though the site's claim to differentiation is that it can predict whether air fares or hotel prices are going up or down to help travelers know when to buy. The acquisition follows a previous deal which already made some of Farecast's technology available on Microsoft's own MSN travel site. It also marks the software giant's return to the online travel reservations business after it spun off Expedia in 1999.