The Nexus One's hardware supports wireless N networks. The phone's software, well, sort of. But! Super-fast Wi-Fi may hit the Nexus one in the next Android update - and if you're feeling adventurous, you can have it sooner.
Google and Broadcom have just released a new wireless driver, which evidently makes the Nexus One much better at connecting to 802.11n networks. (Previously, Google had taken N support off of the Nexus One's official spec sheet, and users reported inconsistent results in connecting to N networks.) The driver, when sewn into a current build of Android, enables N networks across the board.
So, theories: Google is prepping to roll this driver, finally, into Android, just in time for the 2.2 release, codenamed Froyo. Or this new driver incidentally improved wireless N performance, which will remain a silent, uncertain feature on the Nexus One for the foreseeable future. Either way, it'll end up in custom Android builds like Cyanogen's in short order, so you'll be able to try it yourself. [AndroidandMe]