The dates I listed for AMCAS/Interview/Acceptances are accurate +/- one week.
I interviewed at Harvard, UVA, Tufts, NYU, Columbia, Upenn, UCSF, and WashU. These were my impressions (best to worst):
UCSF : The students seemed happy, friendly, and laid back. They work very hard while maintaining a balanced lifestyle.
NYU : Very friendly and active student body. However, the students live in the same building as they attend classes, and for some people, that could get claustrophobic.
Columbia : Very friendly and active student body. Some people find the students are a bit preppy and snobby, but not to an extreme. Overall, this is a school for bros, not dudes.
Tufts : The students seemed really down-to-earth, and they spoke really excitedly about their professors. (And after meeting the anatomy professor, I realized they weren't just talking the place up). The part I didn't like about Tufts is that it's in Boston (where I am now) and I'm looking for a change of environment. But, Tufts is in Chinatown, which is pretty sweet.
UVA : I really liked this school. The students are pretty cool. However, UVA is lacking in diversity. Imagine a room full of white, blond, preppy Virginians. They have the same middle-class VA upbringing, and they each play a sport and volunteer with their token service organization. These are your classmates. I fit this description pretty to a tee, but I would be bored stiff if I went to school of clones.
UPenn : My UPenn interview was unfortunately scheduled. I had to take a red-eye flight back to boston two days prior to my interview, and then I spent the next night on the train getting to UPenn. As a result of the sleep deprivation, my memory of this school is a bit hazy. I remember that it was impossible to find a student willing to host an interviewee for the night (I emailed 4 people, 3 weeks in advance). I also remember the entire school smelled like bacterial culture plates. Regardless, I enjoyed the 2nd-yr lecture that I attended, and the students I met seemed cool enough.
Harvard : I interviewed with HMS for only MD. However, of the students I met in Harvard, the only ones who showed any spark of life where the HST md/phd students. Every single HMS student (tour guides included) seemed really stressed, tired, and spacey. I'm not certain they even liked attending very Harvard. The HST kids, however, where really friendly.
(also, for Harvard interviews, be prepared for a poorly-run day. About half of those in my interview group had interviews scheduled during the morning informational session. Additionally, you have to take cabs across Boston to find your interviewers. And the tour guides will be late.)
WashU : Our tour guide said that after two years at WashU, he regretted his choice to even go to medical school. Also, they have an unhealthy fascination with numbers at this school: WashU is more excited about their students' MCATs and board scores than about their students' residency Matches. Consequently, washU boasts relatively few international or community-based health organizations that would improve their student's medical capacity.