Check your 3DS. You might have some free games waiting to be downloaded.
The 10 NES Ambassador games, revealed yesterday, are becoming available in North America today. However, it appears they might be slowly rolling out throughout the day.
The method for downloading the games is unfortunately obtuse. You have to go to the Settings/Other menu, and then sort through your Your Downloads. If you have a long list of downloads, you likely have to scroll to the end to find the NES games. You have to repeat this for each game. However, you can use the Menu icon on the main screen of the eShop to expedite the process slightly.
Additionally, the Ambassador Certificate is available for download. This allows Nintendo to send you SpotPass notifications about the Ambassadors Program.
Good luck, intrepid ambassadors!
Watch a video of the download process below.