Just thought I'd mention that Radio Comix does four anthologies. None of them are "highbrow" like Raw, Negative Burn, Blab or what have you, but considering the fact that most anthologies seem to die coughing blood, they do okay. Of course, they are very very niche market genre-based anthologies- one funny-animal, one for manga/American manga, and two adults only anthologies, but they have been coming out steadily for years now.
Furrlough, the funny animal anthology just published its tenth anniversary issue and is on issue #107. Mangaphile, our manga-based anthology, is on issue #13 (it's quarterly-and the youngest of our anthologies, at only two years old). The two adult anthologies are on issue #50 (nine years) and issue #25 (four years) and are published under our adult imprint (Sin Factory). Obviously, since they are such specialized genre-type anthologies, we aren't going to appeal to every new artist wanting to break in to the industry, but we've published a lot of new talent in those anthologies- and a lot of those new talents have also branched out and done their own series or books. (Scott Mills does books for Top Shelf, and still does the occasional short piece for Furrlough, for example.)
I agree with the previous posters that a) you are going to be finding new ideas and new talent primarily in the independent end of the comics pool, and b) yes, it does seem the majors aren't really looking for new people or new ideas. Superheroes are nice and all, but I like other genres of comics. After all, I'd hate to go to Blockbuster Video if the only type of movie I could rent was westerns, with no other choices.
--Elin Winkler http://www.radiocomix.com