It looks as through Twisted Pixel’s Kinect title, The Gunstringer may be released via XBL Arcade, according to a listing which popped up on Xbox.com which was later pulled.
Found by Joystiq, if the listing was correct, it would be the first American-developed Kinect title released specifically and confirmed for XBLA.
When announced earlier in the month, distribution methods were not touched upon, so it may still see a retail release, if but past Twisted Pixel titles are anything to go by, it will be a digital release only.
So, still keep this is in the rumor file for the time being until something more official is announced.
Luckily, we took a screenshot of the listing before it was pulled and posted it for you below, along with the subsequent “oops” post from MS.