If you are curios about Junyoung Choi, here is some information. His name is actually DieDi Liu (so he is Chinese or Taiwanese)
“T&G model Diedi Liu, is confirmed to be debuting under M&D ent. He will officially debut in Korea and China respectively on 5th Feb 2012 and 16 April 2012, by releasing his first mini album “First Empire”, which consists of 4 brand new songs. Other details of his debut are not confirmed yet and would be announced on a later date. Thank you.”
Here is his Twitter http://twitter.com/#!/Diedi9310
Here is his Facebook page for more information http://www.facebook.com/OfficialJunyoung
DieDi is in this video
They are saying he is definitely not a girl.
Choi Junyoung was rumoured to join Boyfriend but it has now all been confirmed as false.