Only 8 pictures of the day left until the 3DS release, but they won't be the last of them, as Sakurai will likely start posting about secret characters and unveiling more details on the Wii U version of the game.
It's possible that the Wii U version might have the entirely roster unlocked right away. Then again, there may be people who will only buy the Wii U version and Sakurai may want to avoid spoiling those people too. In other words, pictures about secret characters may only start appearing after the Wii U version's release.
Perhaps, secret characters' profiles may be added, but with a spoiler notice.