John Battelle was quick to announce Yahoo's new desktop search product. They decided to buy rather than build. Yahoo licensed X1's search application and are rebranding it as their own.
Todd Bishop (Seattle PI), Danny Sullivan (Search Engine Watch), and Charlene Li (Forrester Research) have informative details.
See also Gary Stein's comments after Copernic was acquired when he said, "Desktop Search has fully entered into the world of hype ... There's not really a revenue model from Desktop Search."