From Jay Glazer's Twitter feed:
Got somethin else for you guys, jets& bolts on verge of trade. cromartie goes to jets in exchange for a high pick in 2011 draft. 2nd or 3rd.
Even if the Lions were interested in Antonio Cromartie, I for sure wouldn't want them to give up a second-round pick and probably wouldn't want them to give up a third-rounder for him, either. Although the pick would have been in the 2011 draft and not this year, I still don't think it would have been worth it for the Lions.
UPDATE: Adam Schefter reports that the compensation for Cromartie will be a "2011 third-round pick that could turn to a second."