New Google service challenges Yahoo Groups: "Taking on Yahoo in yet another field, Google is testing a service that lets people create e-mail discussion groups."

"Google's service will compete directly with Yahoo Groups, a cornerstone of Yahoo's Web community services. That front is only the latest in an ongoing competition between the two Internet companies.

"In the past five and a half years, Google has morphed from a straightforward Web search engine into a network of Internet services, many of which rival Yahoo's. Overlapping services from the two companies include a comparison-shopping engine [Froogle vs. Yahoo Shopping], tools for Web publishing [Blogger vs. GeoCities] and, most recently, free Web-based e-mail [Gmail vs. Yahoo Mail]."