According to a recent Career Builder study of hiring managers and HR reps, YES, they do.

According to the study, 22% of Hiring Managers say that they are less likely to hire a candidate who does not send a thank you note. Of that 22%, 86% of them give the reason for not extending and offer is that not sending a note shows a lack of follow through, and 56% of them say that not sending a note demonstrates that the candidate isn’t serious about the position. But, you can email the note most of the time, as 89% of all Hiring Managers say that an emailed follow up note is just fine. Of course, that means that 11% don’t like the note to be emailed, and prefer it to be snail mailed. You'll just have to figure out which 11%, take your chances, or to be safe, snail mail all of them. You may even want to email them, and follow up immediately with a snail mailed note, just to cover all those bases.

According to the same study, on a resume, a bullet pointed list of accomplishments is what catches the Hiring Managers eyes the most, and 20% say they spend 30 seconds or less looking at a resume (see Write A Resume That Sells You!)