I was pretty faded when I saw their performance on a late night show. I'm pretty sure it was Jimmy Fallon.

It was a dance-punk style. The lead singer had crazy dance moves. It was all very rhythmic with a bombastic chorus. Toward the end, some guys dressed in African tribal attire came out with drums too.

I remember hearing their name announced and thinking, "Oh, I've heard good things about this band. Let's pay attention." And I really liked it, but it's completely fallen out of my head. Can anyone help?

Probably Cut Copy, who are awesome. They played their song "Take Me Over", a highlight of their new album, "Zonoscope". If you want to get into them, I suggest you check out their 2008 album, "In Ghost Colours" as well.

When in doubt, check Wikipedia's list of episodes for a talk show (in this case, Jimmy Fallon), where they list the guests in each episode:

http://en.wikipedia.org/wiki/List_of_Late_Night_with_Jimmy_Fallon_episodes

Cut Copy did appear on the March 25 show.

Thank you. I forgot that Wikipedia is on top of pop culture. It was Friendly Fires doing their new single "Live Those Days Tonight". Ya'll should check it out.