I've only done I've Got A Feeling on Medium and Hard. For the other two I've completed Easy. It's hard for me to say which moves are new because I haven't done every song at every difficulty that came with game yet.
Here's a breakdown of Black Eyed Peas' I've Got A Feeling (2 bar difficulty):
(easy moves): Smooth, Tell 'em (with side step), Drag In, Scoop Hop, Jazz Square
(medium adds): World, Cheer Push, Ditz, Sway Roll, Sweep, Rodeo, Half Star
(hard adds): Drum Line, Shoulder Sway, Hip Check, Fill Up The Cup, Quick Shuffle, Burn The Roof
I found Cheer Push and Ditz difficult the first few times, Ditz still gets me as does Jazz Square at times. I have to assume Fill Up The Cup and Burn The Roof are both new as they are lyrics in the song (like the Word Up move in Cameo's song). Quite a few of the other moves were new to me, but again, I just might not have seen them yet in the regular game, like: World, Cheer Push, Ditz, Drum Line, Half Star.