Rivals Yahoo and Google launched assaults on each other's territory as the fight for the Internet search dollars heated up

Yahoo's one-two combination began when the Cable News Network's online arm tapped it to replace Google to power its search results. The switchover, which went live Wednesday, means that Yahoo will provide algorithmic and paid results whenever CNN users conduct a search query on the site. Yahoo will also begin offering "virtually unlimited storage" for its paid e-mail customers and will upgrade free users to 100MB from it current 4MB, in a challenge to Google's Gmail service. The upgrade is part of an overall enhancement for Yahoo Mail that will launch this summer. The announcement comes a month after search rival Google said it would launch a free e-mail service called Gmail that offers 1GB of storage. The company's decision to boost its e-mail storage is not surprising. A day before Gmail details were unveiled, Yahoo sent e-mails to some customers in hopes of gauging their interest in receiving 100MB of storage. Google fired back by beginning testing of a service that lets people create e-mail discussion groups. Called Google Groups 2, the service lets people create, search and sift through e-mail mailing lists. People can also subscribe to and monitor groups of interest. That service will compete directly with Yahoo Groups, a cornerstone of Yahoo's Web community services.