Other than getting the promo t-shirts late, Free Comic Book Day went very well for Gabriel Hagman of DreamStrands Comics in Seattle, Washington:

I have to go on the record regarding the Free Comic Book Day t-shirts.  I ordered several of these, fully intending to have my staff and volunteers wear them on FCBD so that customers would be able to easily identify the people who would be able to assist them.  Hey, guess when I received them?  TODAY!  Tuesday, July 6th!  Gee, that's only a little late, isn't it?  I'm in Jim Crocker's corner for these being fully returnable.

Other than that, Free Comic Book Day went smashingly for my little shop.  We had lots of game demos and tournaments scheduled.  We set up under a pavilion outside which helped draw interest and noticed a significant percentage (well over 50%) of new customers.  I'm not sure if the Spider-Man 2 movie really helped in any way other than a general awareness of comics.  We had a much higher response to the television ad we ran on Cartoon Network and Sci-Fi for the two weeks prior to FCBD.