Buying PR In Blog Posts?

I suppose that I should have known this was going on, but I just got an email titled "Sponsoring a blog post," which says:

My name is Samantha and I work for a management consulting
firm. We are currently in the process of growing our online presence and would
like to know if we would be able to sponsor your upcoming post. The sponsorship
is not a product review but rather a mention within the body or the byline of
the post. Do you think we would be able to work something out?

I was a...