Xirrus, the company that is providing the Wi-Fi conductivity to Interop, is well aware of that. According to Bruce Miller, director of product management, the company's 802.11a/b/g/n Radio Module for the Wi-Fi Array will enable the Xirrus Wi-Fi Arrays to be 802.11n-capable with a minimum of effort (and expense). Basically, Xirrus has manufactured the modules so that the capacity for an upgrade is part of the architecture. The arrays will be able to be field upgradeable -- in other words, you won't have to replace the entire device for the new standard.
(Four of the Wi-Fi Arrays are even now hanging --according to Miller -- from the ceiling of the show floor, providing wireless connectivity to those below. I found one of them a few yards away from the Xirrus booth; it looked a bit like a tiny UFO, its lights blinking down at the Internet-dependent crowd below.)
Xirrus has the right idea -- and I'm sure there are other enterprise-level companies that have the good sense not to jump at the new 802.11n standard before it's ready for prime time. It's good that the Standards Committee has offered at least some level of standardization so that unwary consumers and enterprises eager to grab at bleeding-edge technology won't be investing in hardware that will suddenly be declared past history only months later. However, those who will really benefit from 802.11n might be well advised to consider carefully before they purchase -- no pie is ready to eat until it's out of the oven.