I read on Flash Havoc that Yongnuo is expected to announce a new flash transmitter for their YN-622Ns in October 2013.
http://flashhavoc.com/yn-622-tx-transmitter-with-lcd-coming/
(if you follow flash equipment, this is a great site that I recommend bookmarking)
For anyone who's read up on the YN-622Ns, they are a cheap alternative to radio poppers or pocket wizards, offering full i-TTL control of Nikon flashes off-camera - effectively replicating CLS functionality over radio so it doesn't have to be line-of-sight.
In order to transmit up to this point, you either had to learn an arcane system of button pushes, or you could mount an SU-800, SB-900/910 or SB-700 on top of a YN-622N mounted on the camera. This works really well but is a bit bulky and does effectively take one of your flashes out of commission (you can fire it from on-camera, but this isn't ideal). The new transmitter will provide an SU-800 like interface and will attached directly onto the hotshoe (rather than sitting on top of the YN-622N). This will be more compact AND will free up another flash to use off camera!!
I'll write more once I see an official announcement from Yongnuo.........
until then....happy shooting!