Nintendo will begin distributing NES games on September 1 and these are the ten titles Japan gets:
Super Mario Bros.
Donkey Kong Jr.
The Legend of Zelda
NES Open Tournament Golf (aka Mario Open Golf in Japan)
Zelda II: The Adventure of Link
All ten games will be barebones releases at first without digital instruction manuals, emulator features like save states, and the ability to transfer games to another system will be added for free at a later date. Nintendo plans on selling Famicom and NES titles for the 3DS on the eShop, but have not set a specific launch date.
At the moment this news is just for Japan. However, Nintendo kept the ambassador list for the first five titles consistent across regions.
Update: Nintendo of America have confirmed that their list of Ambassador games is identical to the Japanese one.