The show, originally schedule for last weekend at the Hynes Convention Center, was postponed following the tragic events of the Boston Marathon bombings. Following the postponement, many of the guests who were scheduled to appear hit local comic shops last weekend with a "the show must go on" attitude.
While the date and location have changed, it sounds like the organizers are still determining who will attend, per a note on their site: "We are still in the process of reconfirming and adding both celebrity guests and comic book creator guests. Please be patient. We'll keep you updated."
Update: Per a press release, the BCC folks confirm several folks will still attend: George Perez, Mike Mignola, Mark Bagley, Bill Willingham, Tony Daniel, Ed McGuinness, Tim Sale, Steve Niles, Colleen Doran, Aaron Lopresti, Don Rosa, William Stout, Amy Reeder, David Mack, Mike Choi, and Joe Eisma.
They've also added several guests to the line-up: Dan Didio, Phil Jimenez, Brian Azzarello, Dave Johnson, Dan Panosian, Cully Hamner, Barry Kitson, Paul Gulacy, James O’Barr, Howard Chaykin, and Michael Golden.