Sending a thank you note after your interview is a very important step in your job search.

Job seekers should always send thank-you notes, even if they felt the interview was less than a positive experience. It may turn out that the job seeker was not a good fit for that particular job, but could remain in the mix for something else. Sending a thank-you note and keeping the contact is important for that reason and others.

You got a business card from the interviewer and know their name. Mail should get to them, standard business procedures. They may not have the final say, but the thank you will be noticed (it's such a rarity). Even if they say we will call you, you should ask, could I call you next week to follow up and answer any other questions you may have? The point is to show genuine interest in the company, as well as the position in which you are applying for. Its amazing how far a little courtesy and interest can go. When you do a follow up call, you can ask (even if you are not selected) could I call you in a month or so, just to see how things are going and if there are any new opportunities of interest. The candidate hired might not last through the probation period. You're suddenly the new #1 candidate.