I spent a while when I was trying to find a job trying to comes to terms with that "average dev salary" number, since the vast majority of jobs for an entry level position were at least 80k, with plenty being more (I was looking nationwide, wanted to move out, didn't care where). I think it's heavily biased by the fact that the field is growing at an extremely fast rate relative to others, which means the average software dev has dramatically less experience than an average, say, accountant.

So when looking at salary figures, the only sane way of doing it is to control for experience level, otherwise the variance in the explosive growth of the industry will dominate your results.