Here’s a bit of cheery news from the Web 2.0 Summit: AT&T Mobility President and CEO Ralph De La Vega just told interviewer Michael Arrington that the company is working with Apple to let the iPhone serve as a tethered wireless modem for laptops soon. And he says it’ll be available “soon.”

There have been rumors that this was in the works for a while, but if anyone at AT&T or Apple has made it official until now, I managed to miss it.

There are at least two existing tethering options for the iPhone: NetShare and iModem. The former was removed from Apple’s iPhone App Store and the latter only works on jailbroken iPhones; both violate AT&T’s terms of service. Even if AT&T wants more money for a tethering plan–and I’m assuming it will charge something like $50 or $60 a month–I think a lot of people will sign up.

One major remaining question: Given that Internet access on an iPhone 3G can be pretty sluggish, just how quick will it be if a meaningful percentage of iPhone users are routing their connections to laptops and doing things that are even more bandwidth-hogging than typical iPhone tasks?

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