I think the oddity is how popular a franchise it is while having a female lead and not being solely focused on romance. There is romance, but from what I've read so far Katniss really would rather not have anything to do with it.
And then there's the subject matter. For some reason teenagers killing each other on live tv piques the human psyche.
I dunno. Would The Hunger Games be as popular with a male lead?
Would Twilight be as popular with a male lead?
Would Harry Potter be as popular with a female lead?
I think it all comes down to this: THG has fans that aren't just screaming fangirls, so if the roles were reversed the story would still probably stand up. Like, 90% of Twilight's fan base is screaming fangirls that are putting themselves in Bella's place -- being fought over by two hot guys. If the gender roles were reversed, Twilight would lose pretty much 90% of its fanbase. But it also might gain a new fanbase. Harry Potter on the other hand would probably be fine if the gender roles were reversed. Sure the story/emotional stuff would change slightly, but it would be basically the same. The story/magic is the important aspect here, so I doubt it would lose any fans.
Not saying anything is better or worse, just that they're different.
Really, I think what is all comes down to is story. If it's cool and interesting and compelling, it doesn't matter whether the main character is a male or a female. But it does seem easier for men to enjoy male characters. Maybe that's how THG got so popular, Katniss acts like a guy most of the time lol.
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http://img.imgcake.com/crimjpgpe.jpg Mo' buildings mo' problems
ocean kinda grew on me like a flesh eating ...fungus. -BIGPUN9999