The next Free Comic Book Day will be May 5th, 2007. This coincides with the release of Sony's Spider-Man 3, the next release in the strongest comic-related movie franchise.
Although it's not like FCBD needs the help, it does quite well on its own. Of the approximately 2,000 stores that participated in FCBD 2006, 75 percent of them noticed a bump in customers as a result of the promotion.
Spider-Mania can only help FCBD. The film will introduce famed villains Venom and Sandman into the mix, and debut day-and-date on IMAX with the regular release (see 'ICv2 News - Spidey-3 Gets IMAX Release').