Oh you will love them! They had such awsome stage presence! Do let us know what you thought.
I really enjoyed them. They slowed down a lot of their faster songs (most notably Killers and 40') which was unexpected, but still very cool. Hammerstein was a great venue for this show -- despite the fact that it was sold out, it wasn't suffocating, and their was a big venue for FF's big sound.
Does Ben Gibbard really do that weird side to side swaying thing on stage, or does he save that for Letterman?
There was a bit of swaying but not so much that I actually remarked on it until you mentioned it. I think that Gibbard & co were really nervous about the Letterman show. Gibbard remarked that they had done the show earlier that day (yesterday) and that he didn't think that Letterman had really liked them because he didn't get out of his chair to shake their hands. To which someone in the band replied "Well fuck him".
Gibbard does have some really wierd stage manners though -- between songs he says things like "Thank-you, you're being really gracious". Umm . . . I understand that you're not a typical pop star, dude, but the Seattle "just an ordinary guy" thing may have been taken a little too far what with the thousands and thousands of baying fans. Of course, I guess it's just part of his charm, and it does appear to be genuine.