While John Dewan (the Dean of Defensive Studies) says that Teixeira is not any better at scooping low throws than Giambi, it's his ability to field grounders that sets him apart:
The true difference between Gold Glover Mark Teixeira and Jason Giambi is in handling grounders. In the last two years Teixeira has saved his teams 18 runs fielding grounders, while Giambi has cost his team 18, a 36-run difference in Defensive Runs Saved.
- Though the homerun rate is incredibly high at Yankee Stadium, the ball is not carrying any farther than a normal ballpark. It's the close fences that are causing the long-balls. So says Univ. of Illinois Dept. of Physics Prof. Alan Nathan (h/t to PA):
The clear winners (i.e., the easiest places to hit home runs) are Denver and Boston at just under 99 mph, and the clear losers are Atlanta and Arizona at about 103 mph. The spread between winners and losers is about 4 mph, corresponding to a distance of about 20 ft. Note that Yankee Stadium is in the "winner" category, with only five parks having a smaller mean v0. This result, when combined with the below-average carry in Yankee Stadium, seems to suggest that the large number of home runs there are due to close fences rather than abnormal atmospheric effects.