For some reason it just hit me that it really was a long time ago since I used any specific color for visited links in a web site. How so?
I guess in my case that at work I usually work with corporate web sites, intranets and their likes, so a color for visited links has seldom been applicable in those cases. For this web site, I have chosen to have just one color for links (within texts; navigation items have other colors), so it hasn't happened here either.
As I thought more about this, it eventually led to the question: Is a different color for visited links actually of any usage?
Surfing around on the web, it seems that it becomes less and less common, as opposed to the advent of the web, when all of them had it. I don't know if it's out of negligence or if it's a deliberate decision, and also I'm not sure what conclusions usability studies have come to, but spontaneously, right now, I think that, often, there's no need for distinctively marking them up. The reason is that, even though it reflects that within the last week or so, I've clicked on some of the links, I usually can't remember where they led. I click a lot of links each and every day, so there's no chance to map up the entire Internet in my head.
In a case such as Google, at first it seems a good thing that the the search results I've previously clicked are colored differently, but then I soon realize that even though I apparently have clicked those links, I don't know if I was content with the web sites they took me to or not. So, from there on, my actions can take two paths: either click on the same links again, hoping that they actually gave me the answer I was looking for, or just viewing undesired results yet one more time, lured on by the false pretense that I at one time was satisfied with them just because the web browser shows me that I've been there before.
And from a design perspective I think a web site feels more consistent and, basically, good-looking if links have the same color, visited or not. A different color for them would just be yet another color added to the web site color scheme, and it might give an impression harder to grasp.
I have to admit, though, that these are just thoughts. I have no actual facts to back up on standpoint or the other, there are just ponderings going through my head. Do you know what's best for usability? What are your thoughts, weighing in all factors?