Joey Manley, webcomics entrepreneur, posts about "analyzing the market" which he defines as webcomics portals, aggregators and technology providers. (Which as Manley notes is a bit different than the questions an individual creator asks themselves when working on a comic) In the comments there's some talk of Web 2.0 as well which I'll tie into things later on.
First off, I can't imagine any content-related business that isn't going through wrenching changes with the advent of the Internet as THE platform for delivery along with other non-trivial economic trends like… globalization, for starters. Perversely though, comics (and webcomics) have the benefit of being long-time business losers (with arguably the exception of two companies) on a steady decline. So at least comics has the odd benefit of not having to fight incumbents entrenched in an old paradigm. Instead it has the even harder fight of creating a bigger than niche market in this new post-Internet world.
Put this in perspective – we all know that webcomics have flattened the barrier to entry for creators. You want to create and distribute a comic world wide? The Internet allows anyone to do that. It's eliminated the need for traditional publishers, distributors, retail outlets, etc. What has emerged are companies like Keenspot, Modern Tales, Drunk Duck that facilitate the independent creator's ability to distribute their comics over the Internet. But none of these webcomic companies have the same kind of relationship to creators as traditional publishers, etc. do.
In the "space" of comics/webcomics, I think there is potential for non-creators to provide services for growing the size of the market for comics overall, but I suspect these non-creators are going to have to demonstrate their value in terms of growing the overall market for comics because by definition (if these non-creators are not charities then they need to make profits), they are going to add cost to the no-cost chain of creator-website-reader. I'm also not sure what exactly these "services" will look like, but again unless they provide a tangible return for their cost, creators will likely not opt out of the no-cost chain of creator-website-reader.
Manley as a businessman is interested, presumably, in having a growing business – businesses with seriously big rates of growth are the ones that tend to attract investors and even turn into big money for the hard work the entrepreneur puts into it. Are comics that kind of business though? Not all "markets" are going to grow because of the Internet – some are just going to have the cost structure stripped out of them and a corresponding collapse of revenues. Journalism, for example, strikes me as an area where it's not clear that we'll ever have in the post-Internet era anything remotely like the newspaper business of the last couple centuries. (We may have, for example, essentially foundation-funded journalism)
And if "comics" are not a compelling growth story then what about Web 2.0 or other ways to sell the story of the webcomic entrepreneur? I think it depends on how large you think a flickr for comics can get (and if it is not so big that flickr itself won't be interested in becoming the "flickr of comics"). These are tough questions to answer and I don't pretend to know how to.
I think the essential point I'm making though is a general one, which is that comics/webcomics creators have no barriers to get their work out in front of a world wide audience now. Non-creators constructing a business in such a world have to find ways to add value both to the market as a whole and to the individual creator(s) that are compelling enough to move (if not) everyone (than a sufficient number) off of the no-cost chain of creator-website-reader.
UPDATE: Joey's writing lots on this topic nowadays: