The fighting game nuts at Eventhubs had men on the ground during a recent location test for the Japanese arcade release of Super Street Fighter IV, where attendees say that, yes, Yang and Yun have been added to the roster.
This was rumoured a few weeks back, and without pictures or official word from Capcom is still technically a rumour, but you'd have to say that with multiple reports directly from the location tests, this is the next best thing.
Yang and Yun originally appeared in Street Fighter III, and while not exactly the most recognisable or popular characters outside of the hardcore Street Fighter fanbase, within that fanbase, it seems to be a pretty smart decision on Capcom's part to include them here.
To read more about the new character's moves - as well as other changes made to the game for its arcade release - head to EventHubs at the link below.
Updated: Yang, Yun in SSF4 arcade, list of changes [EventHubs]