It's been more than a month since Nintendo promised to restock GameCube Controller Adapters for the Wii U, and now it sounds like the company is making good on its promise. NeoGAF user NR1 shared a photo of the Wii U section in a Best Buy located in Dallas, which very clearly has six adapters hanging on the rack (see above). If restocks are happening there, it's a pretty safe bet to assume they're happening throughout the country at this moment.
Since the adapters are the only official way to use GameCube controllers to play "Super Smash Bros." for Wii U, they've been far more popular than your everyday, run-of the-mill accessory. But while the GameCube controllers themselves have been in ready supply as of late, the adapters have not. Sounds like fortunes are finally changing for those who prefer to use the "old school" controllers to lay down their SSB beatdowns.
Of course, there's no telling how quickly this new wave of dongles will disappear. Just remember that there are other options out there: Mayflash is selling its own GameCube adapter, which also allows you to use your controllers for PC gaming, as well as for the Wii U.