The Internet's good for more than playing games, creating a new virtual you, or watching videos of cats falling asleep. In the business world, the Web has made it easier to deliver corporate software applications without forcing users to purchase expensive software packages.

Salesforce.com (NYSE:CRM) is a leader in this promising field. Providing attractively priced Web-based CRM (customer relationship management) solutions without a large up-front investment has made it one of the fastest-growing software companies -- and no doubt the fastest of its size -- in the country.

Small and medium-sized companies have flocked to Salesforce, but heavies like Alltel (NYSE:AT), Expedia (NASDAQ:EXPE), and AMD (NYSE:AMD) are also clients.

Salesforce is great, right? Well, not all Fools seem to agree. Tom Taulli is bullish on Salesforce. I'm bearish, believing that its shares are richly valued given the competitive landscape. Where do you stand? That's what this Duel is all about.

Duel on!

Longtime Fool contributor Rick Munarriz does not own shares in any of the companies in this story. Alltel is a recommendation in the Income Investor newsletter service. The Fool has a disclosure policy.