Well, yes and no. The real question is if a buyer thinks it's important. I got an offer last week for a domain for $450. I pointed out that the domain has a PR2 (And this is at a parking service) and quite a few links back to it and I was able to sell it for about double the original offer. I don't know if the PR and links were important to the buyer, but the fact that those may have value to some people has to help.
PR is NOT just about links. PR is a combination of a lot of things and links are a part of that. The problem with PR having value is that when the domain is parked or has a new site hosted on it, many of the factors that gave the PR are going to change for better or worse. The links to the domain may not change or may not change quickly, but the change in content is instant and may get picked up quickly. Putting a good site on the domain may help preserve the PR, but who knows? Keep in mind that the domain registration also changes so there are other clues that the PR may need to be recaculated.
I would say trying to bank on a domain's PR that you BUY is risky at best. I've seen someone buy one with a PR5 I think, but I don't know if they sold if before the PR dropped. Think about it as if it were a ripe fruit. It needs to get sold before it starts turning brown and spoils.
So the point is that PR may or may not be a good thing to consider when buying, and may or may not help you when selling. Those that know about such things will probably consider inbound links and other factors more than the current PR. One thing for sure is that any PR, even PR0 will not hurt a domain's price.