@swimchris - the US News rank is not particularly effective for evaluating smaller Phd programs or programs that have changed in the last 20-30 years. If you look at the methodology, it is more of a familiarity/reputation poll of a population of people who last formally evaluated a couple of Phd programs when they applied to them 20-30 years ago.
The more reputable ranking is the NRC (National Research Council) rank created by the National Academies (as opposed to a consumer magazine). It is a data driven ranking based on a huge data collection effort done around 2005. It took another 5 years to compile the data and refine the methodology. The results tend to correlate pretty closely with US News for the larger, more familiar programs, but not for the smaller programs.
Based on the NRC rankings, Harvard is at the top, Tufts and Brown are statistically indistinguishable NU is next and Brandeis is next.
Harvard 3-19
Tufts 23-61
Brown 24-59
NU 47-94
Brandeis 92-116
But this is a rating of Phd departments based on 10-year old data. Some departments may have changed and Phd rank may or may or may not correlate to the quality of the undergrad program which depends as much or more on teaching quality than research quality. One also have to take onto account the fact that some programs are more theoretical (better for a career in academia) and some are more applied (better for a career in industry). Then there is the issue of class sizes - Harvard’s intro to CS course has 900 - 1000 students in it… Then there is the fit issue on top of that… All in all one has to be careful in the importance attached to rankings.
http://chronicle.com/article/NRC-Rankings-Overview-/124721/
Here is a user interface for the NRC data that is a little easier to work with and allows you to manipulate the weighting factors in the rank.
http://www.phds.org/rankings/computer-science
http://talk.collegeconfidential.com/graduate-school/1613591-usnews-vs-nrc-r-vs-nrc-s-rankings.html