So. This was mediocre. It wasn't all bad, but it also wasn't good.
The characters were hard to imagine visually for me because there weren't that much descriptive words given (in summary, one's short and lithe, one's tall and fat, two look the same as each other, and the last is a teen) and their behaviour was often inconclusive age-wise - and they also were not too facetted concerning character. The only character I got a better idea of and therefore favoured greatly was the one who was already dead in the story's present-day world. Also, it took the book about 200 pages to actually qualify as a fantasy novel in the way that "fantastic" things happened on page - before that it was basically a variety of Robin Hood and his Merry Men, thiefing about in an imaginary Venice instead of Sherwood Forest and not sharing with the poor that much. At page 350, the actual story started. Having read a lot of fantasy, I can't say the author managed to surprise me though he seems to be a fan of "unexpected twists" and trying to "gotcha" the reader a lot. What he did manage was to put in the worst and most corny final dialogue in a death scene obviously meant to be touching that I've read in a long time (i.e. Bug's death scene).
What I liked about the book were the "flashbacks" to the younger years of the Gentlemen Bastards - I would have enjoyed a whole book about that very much, I think. Also, I would have liked the architecture of a previous people populating the world to be more than just a backdrop because the idea behind this was quite intriguing. And I'm also somewhat partial to the idea of "true names" as the basis of magic systems. Last not least, let me say I enjoyed the fact that basically all female (secondary) characters were interesting and independent beings in their own right, as far as could be seen.

So, three stars and a quarter, I'd say. The author was kind enough not to end this book on a cliff-hanger, and so I feel completely at peace to let the surviving characters sail off to whatever they'll be up to next - and not find out what that might be.