I went through the Field Select Program earlier this summer. My recruiter called it "automatic selection" or "instant selection." Apparently, I am the only to go through the program in the New York district so far. Basically, you still have to do everything (paperwork, etc) required in the normal process. However, instead of waiting for your package to go to the board, your package, if recommended for the field select by your OR, his peers, and his superiors, will go straight to the commanding officer of the district. The commanding officer of the district will then request an interview where he will fill out an overall-person evaluation. If all goes well, he will sign the field select letter, which basically counts as your pro-rec. Then the entire package along with the field select letter goes to CNRC for final approval where unless you really screwed up somewhere, you will receive your appointment.
I was "pro-rec'ed," and I say that with a lack of better terminology, and am awaiting my final select letter as soon as my medical waiver goes through (MEPS fucked up my eye exam). The process truly is MUCH MUCH faster than the normal process, and if it weren't for my medical waiver, I would've been sworn in a month ago (about two month time from start of application to finish, including waiting an entire month for my referrals to send in their LORs). The field select takes the uncertainty out of the application process, so they use it to draw in very well qualified applicants and hope they don't lose them to better scholarship opportunities.
As for the quota, each district has a given number of appointments into this program per year, and judging by what I hear from my OR, the quota decreases as applicants are admitted into the program, and frees back up when the applicant graduates from college. I'm not too sure on that part, but that's just what I've been told.