I tried it out with January's fantasy by Brent Weeks, THE WAY OF THE SHADOWS. It worked great; after I picked Kindle, it took me to the Kindle store; the price was only one dollar, and it downloaded just like any Kindle book. I am eagerly waiting February because that book is USE OF WEAPONS by Iain M. Banks, and I have been meaning to read him for ages without ever getting around to it. This will be a good deal because this book came out last fall, and is currently $9.99 on the Kindle store. In some ways, I would rather have the book be a dollar and come through the Kindle store than to be free and I have to download it and then e-mail it to the Kindle, because that conversion is always a little iffy.
Interestingly, the main Orbit website didn't mention this offer. You have to know to go here to find it. Although on the Kindle store, if you search for WAY OF THE SHADOWS, it comes up as only $1.00 in price, no matter how you go there.
If you're looking for books by Karen Miller or Brian Ruckley, you should check this deal out, because they are March and April's authors, respectively.