[Spoiler (click to open)]
Basically, it's a typical late Bujold romantic comedy of errors, and immense fun. Ivan is his usual impetuous but somehow strangely efficient self, and (entirely for the good of ImpSec) suddenly finds it necessary to marry an exotic foreigner with more than her fair share of baggage. Naturally there are complications, not least that his bride is a fugitive and accompanied by a servant who is not exactly inconspicuous, since her skin is bright blue...
After that things get REALLY complicated.
Great fun, less Miles than usual since Ivan is the viewpoint character, but we do see Ivan's mum at her scary best, and something happens that various characters have desired right through the series.
Only other thing to mention is that it's set slightly before Cryoburn, with obvious effects on the cast etc.
Bottom line, I thoroughly recommend it.