I agree. As nice as a handwritten note is, it generally does not reach a person in time to affect their decision. In an ideal world handwritten would be the way to go, but like said above in some industries decisions are made quite quickly. Whenever I interview people I usually write my evaluation either later that day or the next morning, so a letter received via post is certainly welcome but won't make a difference in my evaluations. That said, a boilerplate thank you email or letter is kind of meaningless to me when I receive them. Following up on a conversation, asking a question, etc.. are what show me that you were actually paying attention and that you valued me taking time out of my day.