I was hoping to find some time to write a preview of the Japan Series, but now that it's started I'm a little too late.
Seibu took Game 1, with Hideaki Wakui trumping Koji Uehara in a 2-1 pitchers duel. I didn't get a chance to follow the game, so I'll point you to English write-ups at Tsubamegun and Japanball.com, as well long and short YouTube highlights.
Despite Seibu's game 1 win, I think the Giants have a slight edge in the Series. I like the Giants rotation of Uehara/Greisinger/Utsumi/Takahashi a little better than Seibu's group of Wakui/Hoashi/Kishi/Ishii, and I think the Giants have a deeper bullpen as well. Seibu scored a lot more runs during the regular season than the Giants, the starting lineups are pretty equal.
Of course, I've only done a really rough eyeball analysis of the two teams, so I could be way off. On paper, this is a pretty even matchup and I hope all seven games will be as close as game 1.