I don't think he's trying to be antagonistic, he's got a valid question. Your offer doesn't actually make a lot of sense. Generally projects are undertaken either because the creator themselves has a specific desire they wish to fulfill OR because there is a specific need that exists within an already established community. Your new forums don't really fit into either of these categories, so it's a little confusing (to me, at least, and possibly to others) as to what it is you're trying to do.
The only thing I can figure is that you're trying to pull a "Field of Dreams" here - you remember, "If you build it, they will come"? Only that doesn't really work so well on the internet... or in the real world, either.
If you're trying to create your own comic community, with a forum acting as a nexus for a collective or community, you're going to need more to offer than a shiny new forum. Just take a look at the more popular forums... you'll note that none of them (well, maybe Something Awful) started as forums-for-the-sake-of-forums. Take here for example - while to most of us TWCL is an awesome forum, there is also that whole "Webcomic List" thing (it's even in the name) that they do, which is a draw to many others.
Whether the rankings add to the forums or the forums add to the rankings is a different debate, but the point remains. To be the nexus of a community, you need to offer more - free hosting, an advertising system, a podcast, a webcomic or webcomics of your own - something to draw people in and make them want to be a part of the community.
What it sounds like you want to do, after reading and re-reading your post, is to offer your forum up to a number of different webcomics that currently didn't have forums of their own to use your forum as their forum - have it be a centralized forum hub where they could run their own forum for their fans and, at the same time, cross-promote with other artists. Am I right?