Google's Grip Tightens

But DoubleClick has designs to sell ad spots generally considered too high-end to be in the usual fodder for ad exchanges, says Lee. Thus the vast scale of advertisers who use Google -- the company has 500,000 clients, he says -- will help entice publishers to put higher-priced ad space onto DoubleClick's system.

With so many bidders, an advertiser may well get higher rates than it could on other exchanges -- or through its salesforce -- but could cut out the commission.

The higher-priced ad spots would create higher fees for DoubleClick -- and allow the company's exchange to stand out in an increasingly crowded marketplace.

Putting together Google and DoubleClick, in other words, would allow the two market leaders to dominate their arenas in new ways.