I just finished this in one sitting and have to give this book the thumbs up. It is different, what with gunpowder mixed with sorcery and social change. Although I would say that the revolution and the idea of a new society were the weakest parts of an otherwise excellent read. I really enjoyed the characters and found myself routing for Tamas, Adamat and Taniel from the get go. Again I would question the logic behind such a brilliant general like Tamas ending up in some of the binds he finds himself in, but it is a minor quibble. Book of the Year for me so far.
I got the other two books in the trilogy as ebooks a while back, but I don't really remember too well the events. However, the ebook of Promise of Blood is only £1.99 at Amazon, so I've bought it and figure I'll re-read that, then move on to The Autumn Republic and The Crimson Campaign.
I've read some of McClellan's standalone novellas and enjoyed those, too - I recall one was about Tanriel in the Fatrastrian war, and how he met Ko-Poel. It was made all the more interesting because the setting was like a bayoux swamp, which was different.
I've just started Sins of Empire, the first book in the follow up series, and am really enjoying, building on what went before and taking things in a different direction. I'm enjoying as much as the first series (if not a little more) and think the selection of characters is magnificent, both old and new.