I honestly (without bias) think the Giants have the edge.
My reasoning is that although Texas had a .270-something BA this year, it was also with a DH lineup, which will be negated for (potentially) 4 games. My guess is the Giants will keep thier same llineup (for the most part) and just DH the pitchers spot.
After Cliff Lee, I think the pitching advantage favors the Giants....personally I'd hav rather seen Cain start Game 1 against Lee, but I guess that's why I just watch the games and not manage them!
I don't look for the Giants to score a lot, I see another series of close games...Giants in 6...with maybe Texas taking Game 1 tonight and the first one in Arlington.