The latest US News ranking has Fuqua listed at number 12 -- not too bad I suppose. The 2010 economist
rankings has Duke at 17. On the other hand -- Business week has them listed at number 6. Go figure! I wouldn't rely too much on these rankings.
I don't think there is any major decline or anything -- I think the ranking is fair. Duke's program is supposed to be stellar for research and the faculty is top notch. But you still got a lot of heavy hitters such as Harvard, Stanford, Wharton, Sloan, Booth, and Kellogg...And more competition from schools like Dartmouth, Columbia, Ross-Michigan, Yale, NYU, Hass...to name a few. Overall, I'd say Duke's ranking is fair IMHO.