Both performances are lipsynced. Except for Tiffany's "DJ, put it back on" part. What was really strange was in the first video (DON), I think Tiffany forgot and started cheering... @_@
http://www.youtube.com/watch?
v=qiLXcR5A7Lo&feature=player_embedded
I actually kind of like the second video because the camera isn't as spastic as Korean music shows.