Ghosts of Manhattan was a lot of fun. Unlike a lot of pulp homages, Mann doesn't try to echo the clunky dialogue and purple prose of the originals. Instead, he makes his book feel the way we remember the pulps feeling, concentrating on reminding us of the best qualities (fast pacing, larger than life weird action) instead of the worst.
I did wonder if too much information was saved until the final chapters, but ultimately, I think he did just enough foreshadowing to set everything up. I really enjoyed this book, and would definitely read future adventures of the Ghost.