Wow. Ancient conspiracies, secret agents and an epic fight all wrapped up in the dawn of the Age of Machines.
Everyone is going to call it steampunk. (And in fact, Dave Thompson in the outro does just that.) That either shows how steampunk has stretched out beyond its usual haunts (if you like steampunk), or how the term is so over-applied that it's useless (if you dislike steampunk).
The story is on the long side for Podcastle, but the time flies by. It makes a good argument for the idea that genre stories need to be somewhat longer than their non-genre cousins. In this case, the story is a novelette rather than the short story you might expect given the amount of action. It spends part of that extra space wisely on natural opportunities of exposition so that we have a clue as to what's happening. It does this compellingly and justifies the length.
I feel silly dinging Daniel Abraham on anything. The story is beautifully written and, on the whole, satisfying. I do have two quibbles though. These aren't really Things To Be Fixed That Would Make the Story Better. They're just things that irked me.
One, I realize that in a good story we should be able to find the ending in the opening. In this case though, the opening completely telegraphs the ending. The notion it expresses, at this point, is a bit trite and related to what actually happens in the story proper by the thinnest of threats. It reads like an attempt to give the story a heft and gravitas that it hasn't earned. The unearned weight actually bothers me more than the triteness. For me, the story might have been more effective without the opening quotation and the closing summation. Either way though, the effect is still a bit '50s SF B-movie. i.e., "The end... or is it?" (Then again, sometimes, that's exactly the right ending.)
Two, it's hard not to think the only reason to hit how attractive Rachel is repeatedly in the story is to underline that these two guys who live with each other, work together and risk their lives together are not gay. They can't be guy because one of them finds the only woman in the story attractive and hints at this constantly. Now, it's extremely well done in part because she's valued for what she knows, what she does, and her spirit as well as for her looks. For me, he's mostly avoided the trap of objectification. But seriously, one could strike those lines out and not miss them. The worst thing that happens in that case is some readers might think Balfour and Meriwether are an item. In the grand scheme of things, is that so awful? (For the record, I personally would not have even without the hinting.)
To be fair, that they aren't an item isn't so awful either. However, it's as if several times in each section of the story, including while they are in the midst of the epic combat against the Big Bad, Daniel Abraham reminded you how much one of our main characters likes scones. That's nice, but what's the point?
Like I said, they're quibbles. If I were an editor, I doubt they'd stop me from buying the story. Still, it makes me want to write the story where we have extraneous asides to establish that a character must be gay just to see what the reaction would be.