So after feeling alll unfulfilled and going on and on about how Gabriel's Ghost feels like it needs another book, I looked at the author's website to find – THERE IS A SEQUEL! Yes! The book is called Shades of Dark (apparently it was renamed from "Chasidah's Choice") and is coming out in July 2008. I feel all better now and take back what I said about book 1 being unfinished. Maybe I should look this stuff up huh. But seriously the book did not say there is a sequel! What would I do without the internet?
P.S. I was on Linnea Sinclair's website because.. I think her writing is like crack. Fun space opera crack.
specficromantic 
Hey Janicu, thanks for reading my books! There are a couple reasons why there was no mention of a sequel in GABRIEL'S GHOST. The big one was that the publisher, Bantam, hadn't bought the sequel at that point. They weren't even much interested. That's obviously changed.
But be warned–Bantam will not put the word 'sequel' or 'series' on a book. At least, last I asked (which was as recently as last month) they said they won't. So even if they had bought SHADES back then, likely they would still not have mentioned a sequel. Why? Haven't a clue in a bucket. That's how they do things.
It's one of the many things an author has no control over (others being cover art, back cover blurb, shelving and the like…).
Hi Linnea! That clarifies things. I wondered if the reason was you hadn't negotiated whether or not there was a sequel, but Bantam not saying "sequel" or "series" I did not realize. Luckily there are author websites to find things out. Yours is very nice.
Thanks for visiting and being gracious about my reviewing. In the past 2 weeks become a fan, I've already read 3 of your books in that time. 🙂