The first post of note is this one.
"Imploring steemians to practice their profession & hone their expertise."
"Connecting steemians in need to steemians indeed."
"Attracting the freelance industry, recruiting agencies and powerful organizations to the steem economy."
Eric is an author who practices his profession on Steemit, as am I, the object of this post was to get his first book back in the public eye. I think it falls in line with your own definition myself. But I appreciate the clarification : )
I'm not so sure it does. Unless it was a commissioned book, I don't believe it's a SteemGig.
If that were the case, anyone who wrote anything on Steemit could consider the post to be "freelance writing", or anyone who posts sketches could call all of their works SteemGigs.