Shouldn't these technologies 'know' that CSS3 is a subject that is changing all the time and therefore providing recent information is more important than for, say, a search query about World War II (which should be really fixed information)?

It looks like current-day SE-technology, or at least all the talk around it on blogs and news websites, concentrates mainly on to interpret the user's search query and how to get as much information about what the user is looking for. My opinion is that there is no universal ratio of all factors that works perfect for every query and topic. Therefore I agree with Joost that for CSS3 it's wrong to give the age of pages and links such a great influence.

And while I'm typing this, I'm thinking: Maybe the search engines are putting in this kind of old results in an attempt to give a complete view of the subject. If someone is looking for information about the ongoing development of CSS3, this result might be very useful!

Despite all the people who say that search engines record your entire link histroy just because it has been mentioned in a few patents, I haven't seen too much to suggest this.

The only thing I have noticed is Yahoo seems to like to wait a while before moving your site up the ranks. What I mean is that you wil have a site that has some good incoming links and it will be sitting below page 10 for a search, but after several months it will start to rise. Also Google have some way of detecting sites that get lots of very low quality links in a very short period of time. The result is they will slow or stop visting your site.