I'm the Vice Convention Chair of Ohayocon, which is a yearly anime convention in Columbus, Ohio. I saw this mentioned on Boing Boing and thought this was a really good idea.
I've been to both anime conventions and literary science fiction conventions, and it seems that today, the kids are overwhelmingly going to the anime conventions. Our convention attendee's average age is probably somewhere around 15-16.
I know there sometimes is tension between the two types of conventions (I've heard people in both types disparage the other), but I don't think there has to be. There's a lot of things that both conventions have in common, and I think it would be in everyone's interest for anime and science fiction conventions to try to do more together.
One suggestion would be to find your local anime convention, and offer to host some young adult science fiction programming - talking about authors, various series, etc. The deep dark secret about most anime conventions is that they're often starving for good programming. If someone were to present an idea for programming that sounded interesting, and would be moderated by someone who is very familiar with the subject matter, I think it'd have a very good chance of being added to the schedule. You could also contact the convention with the names of local authors, etc. and see if they might consider inviting them as guests. You're less likely to get anime conventions to bring in sci-fi guests from other places since they'll be focused on getting guests from the anime industry, but a local guest might be doable. (Just make sure you contact the CONVENTION and not the potential guest if you don't speak for the convention.)
If anyone from Ohio would be interested in trying some science fiction programming at the next Ohayocon, please let me know and I could see if I could get it added. Unfortunately we just had this year's convention a couple of weeks ago, so the next one wouldn't be until 2009.