NYT:

"AT&T agreed yesterday to sell its cable television business, the nation's largest, to the Comcast Corporation for about $47 billion in stock. The deal would create a cable giant with more than 22 million subscribers, almost twice the size of the next-biggest cable operator, AOL Time Warner (news/quote), which was a losing bidder in the deal. [...]

The Internet and interactive television possibilities were a lure to Microsoft, which backed Comcast in the deal. If the merger wins the approval of regulators and shareholders, Microsoft would have its most direct link yet into households across the United States."

I wonder whether Microsoft is throwing good money after bad here (though I don't know what's the direct cost to them in this deal), or if they'll eventually get a return on their cable/telco investments (an open question for years now).

Update: Washtech has more details on the deal's structure.