Philadelphia - Comcast (NASD: CMCSA), the nation's largest cable TV service and a leading provider of broadband access, has signed a deal to acquire social networking service Plaxo, according to a post on the Plaxo blog. While financial terms of the deal were not disclosed, TechCrunch reports that the purchase price was around $175 million.

Mountain View, Calif. - Social networking service Plaxo, which claims 15 million registered users, has been put up for sale in an auction that hopes to draw as much as $100 million, The New York Times reported on Thursday, citing people briefed on the offering. Founded in 2001, Mountain View, Calif.-based Plaxo has raised more than $20 million in funding to date for its service, which helps users keep their online address books updated.

Mountain View, Calif. - Hoping to capitalize on the fervor surrounding Super Bowl XLI but unwilling and unable to shell out millions of dollars for network TV commercials, several Bay Area tech companies have decided to shoot their own low-budget ads and post them on YouTube, the video sharing site owned by Google.