This suggestion is inspired by a gift that I'm going to be getting for Russell and myself for the holidays.
Leviathan by Scott Westerfeld
Leviathan is the first book in Scott Westerfeld's steampunk YA series. Russell and I really enjoyed it (see post) and have been looking forward to getting our hands on the second installment in the series.
Behemoth came out in October and is currently in my Amazon cart (what can I say, I'm a sucker for free shipping). I plan on rereading Levianthan before Christmas so the story is fresh in my mind before I begin Behemoth. I'm sure I'll enjoy it just as much as my first read.