Odd that Cebulski neglects "get in through editorial and learn to write later" as a tip for writers.
It's worth noting that he does tend towards the more manga-influenced and abstractly-stylised artwork when doing portfilio reviews, too, and relies heavily on pre-existing talent pools or local networks of artists to find new talent - even art schools. Marvel submissions policy seems to mirror this process, too - chances are if you don't have published work already or graduated from something akin to the Joe Kubert school, you'll have difficulty getting anywhere with the Mouse of Ideas (do you see?).
I also gather webcomics are frowned upon for some reason or other, but buggered if I can tell you why.