November 20 in Japan.
According to a Twitter post by a former employee/contractor for peripheral maker Keys Factory, the Nintendo 3DS will be released in Japan on November 20, 2010.
The tweet claimed Keys Factory will be releasing eleven accessories on November 20 to coincide with the launch of the new three-dimensional handheld.
Since the tweet was discovered the account which made the post has been removed from Twitter.
All eyes are now on Nintendo, with a conference scheduled for September 29 expected to reveal release information.