Based on forward P/E ratios, Akamai (NASDAQ:AKAM) is more expensive than Google (NASDAQ:GOOG). But Google has intense competitors such as Yahoo! (NASDAQ:YHOO) and Motley Fool Inside Value pick Microsoft (NASDAQ:MSFT), both of which generate huge amounts of cash flows. Akamai's competitors are a relatively small group of unprofitable companies like VitalStream and SAVVIS. If Google had such competition, just imagine what its valuation would be.

Interestingly enough, Akamai has pursued a strategy that parallels Google's. Both companies have built a platform that includes sophisticated software and hardware infrastructures, building an incredible moat. Microsoft is now spending billions to try to replicate Google's operations.

Yes, Tim, emerging competitors want a piece of Akamai's fortune. In technology, advantages are fleeting, and plenty of savvy entrepreneurs, brilliant scientists, and cash-heavy venture capitalists are funding Akamai-killers. The American capitalist system is working its magic.

At some point, competitors will eat Akamai's lunch. There's potential competition from incumbents such as Google, Cisco (NASDAQ:CSCO) and Juniper (NASDAQ:JNPR). Perhaps the most frightening threats come from the upstarts like BitTorrent, the most common sources of disruptive technology.

It's not a question of capital -- the global economy seems to enjoy a nearly unlimited supply. It's not a question of brainpower -- that commodity seems to be booming worldwide. But new technologies do perpetually face one perilous barrier: time.

A new technology might kill Akamai within the next year or so. In the next six months, it's highly improbable. Since Akamai is a stock for momentum-growth investors, its most likely backers don't care about the long-term so much as the next quarter. For the near future, Akamai's technologies are a "must-have" for a surging market. What else could a momentum investor ask for?

Shares of Akamai have risen 141% since being singled out last year in theRule Breakersgrowth stock newsletter service. See David Gardner's other high-growth picks with a free 30-day trial subscription.

Think you're done with the Duel? You're not! Go back and read the other three arguments, and thenvote for a winner.

Fool contributorTom Taullidoes not own shares mentioned in this article.