http://biz.yahoo.com/rc/040116/tech_google_1.html

AN FRANCISCO, Jan 16 (Reuters) - Google Inc (News - Websites) ., which dominates the market for Web search, is developing a service that could dramatically extend the reach of its lucrative keyword-based advertising by linking such ads to e-mail, people familiar with the matter said on Friday.

Privately held Google (News - Websites) , which is expected to go public later this year, faces rising competition in its core search business from e-mail providers including Yahoo Inc. (NasdaqNM:YHOO - News) and MSN, Microsoft Corp.'s (NasdaqNM:MSFT - News) Internet unit.

Adding an e-mail service would provide a potential boost to Google as its technology lead in the search market seems destined to narrow and it prepares to answer to growth-hungry shareholders, analysts said.

The Mountain View, California, company, which has recently made several e-mail related acquisitions, is working on a way to serve advertising to an e-mail at the moment it is opened, people close to the company said.

"I'm sure Google is getting more and more concerned about locking in users. It wouldn't surprise me if they did something very sophisticated with e-mail," said Danny Sullivan, editor of SearchEngineWatch.com, who tracks the industry.
I thought this was interesting...Of course it is from Yahoo (Google competitor) so you have to wonder about the source.