I think vampire stories should be dark, sexy, and cool, and Blood Vice hits them all with force.
The action is riveting, there are some awesome side characters (look for Little Ricky and the Knights of the Thorn), and some really great one-liners (look for the restaurant scene at the beginning of the book).
I was happy the author kept vampirism supernatural rather than going the vampirisim-as-a-virus route, and there are some additional elements of magic and mysticism that broadened the story immensely in a great way. The vampire hit man, Karl Vance, has a witch companion who we didn't learn nearly enough about, and I look forward to seeing her more in the sequel.
It wasn't clear to me when I started reading if the mafia guys KNEW Vance was a vampire or not, and I re-read that great scene in the restaurant when I figured out that they did NOT know that from the beginning. It made the scene even better, but I wish it'd been clearer from the description on the flap so I'd known that on the first read.
I was a little bit lost through the middle part of the book not knowing where exactly the story was headed, but that was definitely what the characters should have been feeling at that point so I suspect that was intentional on the author's part.
I went into this book expecting something like Underworld, which I loved, and it didn't disappoint on that account, but it turned out to be much bigger, badder, and better, and I'm eagerly awaiting the sequel.
This book was awesome, from that quiet scene in a fine restaurant in the beginning, to the fiery, cataclysmic conclusion.