The Iron Wyrm Affair by Lilith Saintcrow
This story punts you out of the plane and lets you free-fall without a parachute into the world. It took some getting used to, but I got absorbed in it. So much so that it was high on my list of addictive reads (I talked about it over at Stellar Four).
This is the first book in the Bannon & Clare series. It's alt-Victorian with magic, gadgets, deductive geniuses, conspiracies against the crown, fantastical creatures, and a team that may or may not be able to trust each other.
I referred to this book in the past as steampunk, but I'm starting to question the use of the genre name. Overall, I don't know that much of us really have a concrete definition of steampunk. I've been thinking about it, and I tend to lump fantasy with alt-history (esp Victorian England or late 1800s elsewhere in the world) and some kind of gadgetry in the steampunk sub-genre. I think this is pretty consistent with your average reader. Purists might be gagging right now, but so be it. Feel free to school me in the comments.
I would say that Saintcrow takes elements of steampunk/alt-history to concoct some bookish alchemy, and I truly enjoyed the effect. I can't say that I understood every reference. There are a couple of lines of dialogue that completely went left when my brain went right. It really didn't matter for me. I rarely understood the techno-gobbledygook on Star Trek:TNG, but I still watched it faithfully every week. The arcane references felt much the same - background detail that the characters knew all about, but weren't crucial to understand the main plotline. What worked was the vivid descriptions and that the world was revealed as the action went along. We didn't have a lot of asides telling us all about the world. I gleaned what I could as the story progressed.
Miss Emma Bannon is a sorceress. A very, very powerful sorceress. She is overworked, isn't sure she can trust her Shield, Mikal, and is still reeling from a traumatic event in her past. Mr. Archibald Clare is a mentath - a deductive genius (think Sherlock) who survives on logic and must have puzzles to stimulate his vast intellect or he might go mad. Throw in an Italian assassin, a German mechanist, and loads of conspiracies and you have one action-packed story.
Now, seeing the line-up with the magical Miss Bannon and logical Mr. Clare, you might be thinking, "Opposites attract, there is going to be some kind of romance here." Yeah, you can think that, but if it's romance you're after, this isn't that book. Not that there aren't developments, but it's not the crux of the story. Can't reveal anymore without spoilers.
Of course, I long ago stopped thinking that I would get the usual from Saintcrow. Now I just sit back and enjoy the ride.