Aged domains are like a yin-yang type situation. On one hand, it's more likely to have authority from previous use, which could be something to build on, if you or the end user plan on using relevant content. Same goes with PR. If the page rank is high, and the domain has not been abandoned for too long, then there should be plenty of backlinks to the domain, which could help the sites search presence.
On the other hand, well, first off, as stated above, is mostly domainers interested in these types of domains or hobbyists. Endusers aren't typically interested in anything other than branding. Secondly, even with high PR, the backlinks from an old domain would be more likely filled with crap sites that actually hurt seo; and the process of having them removed would be a pain in the ass, if not impossible. So, I would check and see the backlinks profile before investing money into it. Banned sites suck, and you're more apt to find ones, since what was considered white-hat seo tactics some years ago, have been since banned by Google, so the seemingly valuable domain that is aged maybe worthless until you convince Google to unban the site
So, the answer is... Sometimes.