Over the last decade, the library of third-party information about colleges has grown exponentially. U.S. News & World Report's annual college guide may get the most attention, but it's a general-interest dinosaur in an ever-expanding realm of niche evaluations of colleges. Now students of all faiths, ethnic origins, and interests can find a guide or a set of rankings carefully compiled--or thrown together--just for them. In academe, diversity is a good thing, but what about in the hyped-up precollege marketplace? As opinionated lists of colleges proliferate in the information age, the cumulative effect seems to be confusion. Amid all the guides and rankings, many students say you still can't learn much about a campus unless you visit it.