Due to "popular demand" the Alliance chopper built for the web series Azeroth Choppers, will be headed into World of Warcraft when Warlords of Draenor launches later this year. Unlike the winning Horde chopper which will be given free to all players logging into the game between now and September 30th, the Alliance chopper will need to be purchased from a vendor and, according to devs, will cost a "pretty hefty sum of gold".
Due to popular demand (and a few shady back-alley deals in Stormwind’s Old Town), the Alliance bike built for Azeroth Choppers will be rumbling its way to a vendor in Azeroth sometime after the launch of Warlords of Draenor. This mount will cost a pretty hefty sum of gold, however, so you might want to start saving up now if you want to ride around in style on this masterful machine.
Source: World of Warcraft community site