.323. I would imagine it is higher for the starters.
Of the 21 SSs that ESPN lists as having enough PAs to qualify for the batting title, the median OBP is Alexei Ramirez's .316. This includes players who have played a lot at other positions, like Jhonny "Spell Check" Peralta. Desmond is up to .315 after his hot stretch.
It surprised me to see that the NL average OBP for SS as SS (i.e., excluding guy time at other positions) is .328, if the ESPN sort is to be trusted. This is higher than the AL's .315. I guess it is the Hanley / Tulo / Furcal / Castro effect. Also, the AL can more easily carry a glove only SS like Cesar Izturis or the mix in Detroit because of the DH.
We have an interesting case at SS. We may have two above average SS. That has to have a lot of trade value when both have plenty of years of team control.
