According to Robert Scoble on Twitter, Google has bought DoubleClick for 3.1 Billion.

What does this mean for MSN?

What does this mean for AOL?

What does this mean for affiliate marketing and CPA??

EDIT: More… here’s the NYTimes article.

DoubleClick’s exchange is different from the ad auctions that Google uses on its networks because the exchange is open to any Web publisher or ad network — not just the sites in Google’s network. Offline ad sales have been handled through negotiation, but the efficiency of online auction systems has caused some advertising executives to consider using auctions for offline ads in places like television and newspapers. DoubleClick’s new exchange could function as a hub for online and offline ad sales.

Implications? Wide.