In his presentation at OSCON, Roger Magoulas, the director of O’Reilly Research, provided some interesting graphs based on our trends data mart. Here’s the 3-year programming language market share trend based on computer book sales:
Also worth noting on this chart is that book sales tend to spike even before the release of commercial languages, as the vendors work with publishers to get books out by the release date, while books on open source projects tend to trail the release date. On the one hand, you could interpret this as meaning that open source is slower to market, but I think it says the opposite: open source projects can move fast, and catch publishers by surprise. Few publishers expected the quick uptake of
Java AJAX and Ruby on Rails.