As I read it on the subway, I noticed how Diplomatic Immunity read differently now that I was familiar with Miles and his universe. What struck me most was the sheer density of references to the wider universe, to characters and human subspecies and empires that had all been explored in previous stories. Diplomatic Immunity has a plot of its own, of course, but quite often I found myself thinking "Oh, that is where such-and-such a person ended up" or "So such-and-such an empire is still that way?"
Bujold's Miles Vorkosigan novels follow a personality trying to define himself. When we first encounter Miles in The Warrior's Apprentice, he's a 17-year-old man convinced that he's a person at terminally loose ends, of dubious value to his aristocratic family and his wider society, uncertain that he could leave any kind of legacy. Through the Vorkosigan novels, we see him work through these issues, as he forges two formidable identities (Admiral Naismith and Auditor Vorkosigan) and goes on to demonstrate just how he is needed. Vorkosigan's story reached its climax, in grand satisfying style, in A Civil Campaign, when Miles' concerns were finally assuaged.
Diplomatic Immunity doesn't add anything particularly compelling to Miles' narrative. Yes, we see that he is happily married to Ekaterin and that he is set to become a father, but I doubt that readers of A Civil Campaign were surprised by this. Yes, we see that Ekaterin is a formidable woman indeed, but we saw her in action as early as Komarr. Yes, we see how wary Miles is of rogue Cetagandans with that empire's biotechnology, but we already saw him be that way in Cetaganda. Yes, we get to see Miles butt heads with Admiral Vorpatril, but he has never fit well into any Barrayaran hierarchy. I've re-read Diplomatic Immunity a couple more times, but my sense that Bujold is mixing plot points from different books remains.
The story of Miles Vorkosigan's humanization has ended with A Civil Campaign. Now that Miles is simply a powerful Barrayaran aristocrat-bureaucrat with a rather more interesting past than most, what more is there to say about the man? I like Bujold's meticulous writing style very much, but is she capable of continuing the story of Miles' humanization or of finding an equally compelling arc? If she wants to revisit his universe, I suspect that she may have to make him a background character, thus treating him like his mother Cordelia. I wonder if Bujold might have been testing this approach out with her enjoyable novella Winterfair Gifts, included in the collection Irresistible Forces, which explored Miles' wedding from the viewpoints of Sergeant Taura and Armsman Roic. For the time being, although Diplomatic Immunity remains above-average space opera, I'm half-tempted to wish that Bujold had written something different. Like Season 6 of Buffy or Season 5 of Babylon 5, as well-constructed as it is Diplomatic Immunity feels like an unnecessary addition to an arc that was already complete.
UPDATE (5:41 PM) : Crossposted at lmbujold.
UPDATE (11:10 PM : Crossposted at rec.arts.sf.written.