What is the biggest challenge facing fraternities and sororities today?

As someone who's not in either, but is currently in college, I would say image. Most people I know who are not in a frat or sorority see them negatively, as do I. The frat boys appear to be hard-drinking, not terribly bright, spoiled by their parents, and primarily concerned with getting laid. Sorority girls also appear relatively dumb, spoiled, shallow, Valley-girl-ish (like Oh My God!), and more interested in getting their MRS than their BA. I know a fair number of frat boys and sorority girls, and although their are plenty of exceptions, this seems to be how they are construed by most college students. They need to improve their image by working on serious projects and standing out as academic achievers, otherwise, I doubt that this stereotype will change.