This website previously had said that "Arrow didn't like range voting" (also known as score voting). And, unfortunately, there were various quotes by Arrow and/or his former student (also a Nobel prize 3-way co-winner!) Eric Maskin that we could use to support that claim... some of them, especially by Maskin, were in my opinion embarrassingly wrong. [For example, Maskin once contradicted Arrow's statement (1) below.]
However, it gratifyingly appears that Arrow has changed his mind. This audio interview of Arrow by the Center For Election Science (you can read our partial text transcript), dated 6 October 2012, was pointed out to me by "omegatron":
In this interview Arrow correctly says that (1) his Impossibility Theorem doesn't apply to range-voting-type systems, and (2) those provide more information than ranked systems. He then says (3) he thinks a score system with "three or four classes" is "probably the best" single-winner voting method:
Dr. Arrow: Well, I'm a little inclined to think that score systems where you categorize in maybe three or four classes probably (in spite of what I said about manipulation) is probably the best.
So I think Approval Voting is a little too coarse. I think if you had three or four candidates the incentives for this would be much less if you had three or four classes.
Dr. Arrow: I think one of them is the question of more information. And scoring methods are a way of getting more information.
About Arrow's impossibility theorem