FOR America\'s colleges, January is a month of reckoning. Most applications for the next academic year beginning in the autumn have to be made by the end of December, so a university\'s popularity is put to an objective standard: how many people want to attend. One of the more unlikely offices to have been flooded with mail is that of the City University of New York (CUNY), a public college that lacks, among other things, a famous sports team, bucolic campuses and raucous parties (it doesn\'t even have dorms), and, until recently, academic credibility.