On Facebook, tens of millions of users have been constructing the social network's most important asset: the social graph. As people add friends, Facebook gets to understand how its users know each other and, ostensibly, earn some money in the process. Google is building a Social Graph API to rival Facebook, although the Web giant is taking "a much different and more open approach" to social graphing. Whereas Facebook operates under a walled-garden approach -- meaning everything that leverages Facebook's social graph links back to Facebook -- Google will allow third parties to grab social graph data produced …

If Microsoft buys Yahoo, AOL could be left behind. Both Microsoft and Yahoo are the Time Warner company's most likely buyers; put Microhoo together and suddenly, AOL looks like "a wallflower at the prom." As one ad exec says, "I now think that [Time Warner] pretty much has to sell, and they also have to sell really quickly...I don't see what else they do." But with the two most likely buyers out of the picture, AOL might be cheap. Who would be interested? Rupert Murdoch's News Corp., always looking for ways to better monetize MySpace, …

The most surprising thing about a Microsoft-Yahoo merger is how little affect it would have on the Internet advertising business in the short-term. True, Microsoft would gain a substantial share of the search market, but Google wouldn't be losing any, and Microhoo's combined share would still only be half that of Google. Worse, the merger comes at a time when Yahoo's search share is on the wane. On the non-search front, adding Yahoo to adCenter would certainly give the combined company a broader array of ad units to offer advertisers, but both companies, despite the breadth of offerings, have …

As many expected, Google swooped in with an offer to help rescue Yahoo from Microsoft's (hostile) takeover bid. This could mean many things. A guaranteed revenue deal, such as the one Google struck with News Corp.'s MySpace, is one possibility, whereby the search giant guarantees revenue in exchange for Yahoo outsourcing part of its ad business. Google could even buy Yahoo's search business outright and then turnaround and sell search and contextual links on Yahoo. But any Google involvement would attract big-time regulatory scrutiny. Meanwhile, Google has already said the Microsoft deal "raises troubling questions," suggesting …

Silicon Alley Insider's Henry Blodget offers three reasons why he thinks a Microsoft-Yahoo union would be a disaster. For starters, he says the deal--though it would eventually pass--would come under at least a year's worth of regulatory scrutiny in the U.S. and EU, as Google returns the lobbying favor Microsoft paid the search giant last year in opposing its proposed acquisition of DoubleClick. Prior to this, Yahoo, will be bombarded with other offers (a potential Google partnership is in the works, for example), further delaying the long integration process even further. The second big problem is that …