In a knowledge base article
updated and posted yesterday, Apple warns MacBook Air users that they might suffer from some issues with the Wi-Fi-related features of the notebook, specifically when using Remote Disc, migration, and remote install of the operating system, if they’ve got older firmware on their third party wireless routers.
Apple asserts that upgrading to the latest firmware of the device will iron out all issues, should any of them rear their ugly heads. We assume that if you own an AirPort Extreme, you have nothing to be worried about.