I don't think it very accurately reflects what's used in real life, either for the innumerable hours of boring everyday programming work that people do or even what kind of code is being cranked out in the major open source projects - the ones that are actually used by other people.
What it does provide is an interesting leading indicator: what's hot right now. Languages like clojure which get a lot of attention for a while but aren't used in a whole lot of real applications tend to peak and then drop relatively quickly.