Have you validated there is a market for this and which segment of bloggers that is? And that people would be willing to pay for reviews of drafts? I'd imagine people like blogging for many reasons including: * it's free-form and easy * it's immediate, i .e. my thoughts on the interweb now * it's free or relatively cheap (less hosting/domain) This concept might fly in the face of some of these reasons so market need…
The huge amount of bloggers makes the market interesting enough. But you are right about the categorization of reviewers.
Bloggers is a highly heterogeneous group so it's important to understand the true addressable market (how many on wordpress, how many write content that is review-worthy, how frequently do they write, do they have their own domain, are they trying to make money, etc etc). Otherwise, it's akin to saying "my market is internet users".