Some inconsistencies with batted ball data forced David Pinto to re-calculate his PMR numbers. The new results are up, with second basemen here and shortstops here. Note that these tables only focus on each players' ability to scoop up ground balls, since catching line drives probably isn't a repeatable skill.
Having converted their PMR into runs saved above and below the positional average, here are the numbers (per 150 games) on a handful of interesting players:
Second Basemen:
Bret Boone: -38.0 (runs below average)
Jose Lopez: +12.5
Nick Punto: +25.7
Orlando Hudson: +17.4
Chase Utley: +16.6
Jorge Cantu: -26.0
Alfonso Soriano: -23.4
Robinson Cano: -22.6
Mark Ellis: +6.0
Shortstops:
Yuniesky Betancourt: +3.5
Wilson Valdez: +11.1
Mike Morse: -24.2
Jhonny Peralta: -19.9
Derek Jeter: -10.7
Mike Young: -26.0
Omar Infante: +24.9
Bobby Crosby: +14.2
According to PMR, Bret Boone was the worst defensive second baseman in baseball last year, and Mike Morse was the second-worst defensive shortstop. Meanwhile, Betancourt looks a lot worse now than he did a few days ago, although he's still above average. As far as I'm concerned, his "low" rating is all sample size, and should be expected to improve by at least 10 runs - but probably more like 20 - in 2006. The same argument could be made about Lopez's unexpectedly high rating, I suppose, but I don't like to think about things that make the Mariners seem worse.
So, yeah. Other positional ratings are on the way, although I probably won't bother converting them to runs saved, because unlike with infielders, balls hit down the lines and into the outfield can often go for extra bases, and it's impossible to know what type of hit a ball would've gone for had it not been caught.