They clearly can't do too much shorting *legally* while there are no (or precious few) shares to borrow, but they can NAKED short the stock still...and plainly are, as GMCR has been on the Regulation SHO list (one of only four NASDAQ stocks there, BTW) for about a week now. It was on at least one time in the past, but went back off within a few days. This time..."it's personal", lol.
It's a damn shame we can't see the number of fails to deliver as it modulates from day-to-day, as that would be a good sign of the shorts' desparation. But you know they've got to be sweating buckets over the threat of increased enforcement of naked shorting, and the up-tick rule reinstatement.
I'm feeling pretty good right now, as a GMCR long. I was driving around today worried my limit orders at 50+ (as per the suggestion posted earlier) would trigger in a short squeeze and I'd lose out on the subsequent run-up! (Okay, it was just a fantasy...)