Supposedly it was going to be Microsoft because they needed the distribution in order to better monetize their ad network;  also I could see the sense in a Doubleclick - Microsoft deal so had expected them to pull the stops out on this one. Microsoft has the passport data, profiling and text ad system, and Doubleclick has prime real estate and an existing distribution network that Microsoft needs to get its volumes up.

But no, Google has fully headed them off at the pass, and if you thought YouTube was big money how about $3.1 in cash.

The combination of Google and DoubleClick will offer superior tools for targeting, serving and analyzing online ads of all types.

"DoubleClick's technology is widely adopted by leading advertisers, publishers and agencies, and the combination of the two companies will accelerate the adoption of Google's innovative advances in display advertising," said Eric Schmidt, Chief Executive Officer of Google. Quote ironically borrowed from Yahoo! news :-)

Damn the markets are flush with cash these days, and I am sure there are now some very happy DoubleClick employees.