This is a difficult question to answer without knowing more about what you are looking for. There are lots of universities with good groups in quantum information. As the other answerer said, Caltech is good with people like John Preskill (theory), but I can't think of anyone there who is really doing experimental work. There's Jeff Kimble and Oskar Painter, who do related work, but not true quantum information. I don't know anyone at Princeton, which is not to say they don't have good people, but I can't think of any off the top of my head. MIT of course, is good, with Ike Chuang and others. The University of Maryland has a number of top people, especially in experiment (Chris Monroe (trapped ions), Trey Porto (atom lattices), etc) but several in theory as well. The U of Maryland recently started the Joint Quantum Institute, which is a collaboration with NIST, which is bringing a lot of exciting people together in quantum information. Similarly, the University of Colorado has a collaboration with NIST called JILA, which brings some of the top people together into one program (Dave Wineland (experimental trapped ions), Ray Simmonds (Josephson junction experiments), Manny Knill (theory), etc). Of course, Harvard and Stanford are great too. The University of New Mexico has a surprising strength in quantum information on both the theory and experimental sides.
If you want non-US schools, there are many of those too. Both Cambridge and Oxford have a number of strong groups. Innsbruck has another top ion experimentalist (Rainer Blatt) among others. The Max Planck institutes. There's the Perimeter Institute in Canada which has a lot of great theorists, and I assume they are somehow attached to some university, though I don't think the Institute itself has students. Jeez, there's a lot of good schools. I could list a lot more, but hopefully this was helpful. And, I admit, having a PhD in experimental quantum information using atom systems, my list of schools is probably a bit slanted towards atom-based quantum information. But hey, that's what you get if I answer...