National Academies/National Research Council rankings of grad programs
In case anyone is curious, it has been 15 years since the national research council released its rankings of university doctoral programs. The new version is now out, and there are now two ranking systems (R and S) for programs. In Ecology and Evolutionary Biology, Duke ranks number 1 in both stats (looking at the median for each). The link goes to the NRC site for the raw data. The raw data are free if you want to get into the real nitty gritty.