One of the colorful characters at the Empress of Mars bar is Ottorino, an Italian fella obsessed with Westerns/cowboy movies. He doesn't turn up right away, which is in some ways a shame, because he's a good signal of expectations: this is a fairly cinematic book. The chapters are not as short as a James Patterson thriller, but they're relatively short, relatively snappy, and much of the sensory detail is visual. But Kage Baker is not the sort of cinematic writer who's been influenced by the last 5-10 years of popular movies and that's it. She knows the old ones, too; she's got layers in her reference points.
Some of the characters are pretty fully realized--the Empress herself, Mary Griffith, is warm and interesting and stubborn as all get-out. But there's a spectrum from Mary to some of the people around her who are types rather than fully drawn characters, and on out into a few stereotypes. I'd be interested to hear the impression of actual Irish, Scottish, Welsh, and other Celtic peoples of her "PanCeltic" language and characters. To me it read rather like the stereotypes of British (in the British Arean Company) and Irish (in the Clan Morrigan and other PanCelts) had been carried on with the symbols reversed: "The Irish are drunks and sweet-talkers, but that's a good thing!"
But then there was the clan chief's son Perrik, who was just himself. I really liked Perrik and his biis (artificial bees, essentially, for multiple purposes), and I wanted more of them.
The word I kept thinking of with The Empress of Mars was "rollicking." It's not a book that's doing something startlingly new, and it's not exploring serious areas of the human psyche, and that's okay; sometimes you need a book that rolls and crashes along with plenty of cool bits with dust storms and "Martian porcelain" and the characters you like getting their own back against those who would oppress them. If this is what people meant when they talked about summer beach reading, I could get behind the beach reading concept.