It's pretty expensive too so yea, very high bomba possibility. There's been a lot of talk about nerds dominating the box office but I'm not sure that's accurate. So far most of the recent, successful comic films attract pretty large female audiences alongside the male demographics; Christian Bale, the Thor guy, etc all generate female interest plus all those films have pretty big romantic arcs. Pacific Rim seems like a pure dudebro cumshot. Sure Idris Elba is in the film, and he's arguably the most handsome man since 2pac, but I'm not sure he's going to get women into the theater. Plus this isn't an established IP/series/sequel/adaption/etc.
Also the lead actor is kind of forgettable, making the film even tougher to sell. Who knows, maybe we'll be wrong. Personally I'm not a "big robot action" guy either, but I like Del Toro and love Elba so I'll be there.