Check out TaeTiSeo's newest BTS Video from their Pictorial for "K-Wave"

Update #4 7/10/12:
 http://www.youtube.com/watch?v=Ma4DfxmK7Vw&feature=player_embedded

Update #3 6/27/12:
 seohyun http://www.youtube.com/watch?v=eMSu-apfR3I&feature=player_embedded

 
Update #1
Taeyeon http://www.youtube.com/watch?feature=player_embedded&v=6b03TAeva2M


Taeyeon  http://www.youtube.com/watch?v=zUMDMZvJA34&feature=player_embedded

Tiffany http://www.youtube.com/watch?feature=player_embedded&v=OcvVayf6naU

Seohyun  http://www.youtube.com/watch?feature=player_embedded&v=sbgmTDdgDyo