Not sure if this is old news or not, just chanced across it while browsing the apple store last night.
http://store.apple.com/Apple/WebObjects/ukstore.woa/wa/RSLID?mco=937D0C07&nplm=D4141
Looks like it is possible to update the firmware in the Airport on the majority of all recent Macs to enable 802.11n on them.
Only a couple of quid, but kinda sucky how they dont just make it a free upgrade.
http://store.apple.com/Apple/WebObjects/ukstore.woa/wa/RSLID?mco=937D0C07&nplm=D4141
Looks like it is possible to update the firmware in the Airport on the majority of all recent Macs to enable 802.11n on them.
Only a couple of quid, but kinda sucky how they dont just make it a free upgrade.