Pre-orders and previews begin April 10, launches April 24.
MacBook Air Domain Names
MacBookAir.net, MacBookAir.org, MacBookAir.us, MacBookAir.info, MacBookAir.biz have been registered by corporate registrar MarkMonitor. Most of the registration information is obscured, but the billing information for several of the domains is attributed to John Donald who carries an apple.com email address. Typically, this information can be faked, but the registration also shares an internal billing ID (MKN-14211616) which is indeed Apple's (based on other domains).
The evidence isn't conclusive, however, as MarkMonitor provides some automated trademark protection services to corporations:
Also continuously monitors new domain registrations that may infringe upon a company's brands and divert traffic to sites selling counterfeit or gray market goods.
So the MacBookAir domain registrations may have been triggered by the MacBookAir.com domain registration - which was not registered by Apple.