There's some great creatitivity in comics/manga especially these days. Comics especially in Japan have taken on a role of becoming a place where any writer can basically put together a story board for a series or movie, not just for anime, but for live action/reality based drama shows as well. Some of them are extremely moving and complex. Most of them most certainly aren't juvenile. You have to know what to look for and what type manga it is of course. There are age groupes and genre depending on how, when. where, by who it's published. There are publishers/magazines that deal with children, young men, middle aged men manga only for instance, or even old men manga.
Comics in Japan have become a great way to gather an audience for a tv show or movie before it's made cause producers can see how popular and who is reading the manga so they can limit their risk.
Comics these days are a far cry from what they were 20 or even 10 years ago. Even in America you have a huge comic resurgance with many tv/movie directors coming out of them and going back into them, like Keven Smith, and Joss Whedon.
Online comics in particular are very interesting, and some have huge followings.
Most comics are republished online, if not on dedicated web sites, in anthologies and weekly updates. It's one of the problems actual paper publishers are facing. In Japan of course you have a huge net cafe audience, so not much as a concern there, but even those are usually translated and upped on different forums like Hongfire within weeks of them being published/becoming public.
