Recent chatter on a professional listserve prompted a New York Times reporter to write about the thank you letters admission officers receive from students after info sessions, tours, and interviews. When I interviewed students at another school, I always sent a little note of encouragement after the fact and often got a thank you note in return. I thought it was a nice practice. However, these days, it seems as though even the simplest act, such as visiting a high school, is deemed thank you "worthy" and the number of letters, and their frequency, is surprising.
If you write a thank you note to someone at UVa, it'll probably get sent downstairs to the file room to be placed in the miscellaneous credentials files. If an application with a matching name arrives at some point, the letter will make it into the application folder, but it won't get much attention considering the other documents in the file.
I guess what I mean to say is that thank you notes are fine to send, but no student should suddenly panic because they haven't been sending notes during their college search. I fear that the New York Times article might make students feel as though this is a practice they "must" to do in order to be competitive. That just isn't the case.