[xaitv]

Based on what I see around me Ruby is used by a couple of big companies, while something like PHP(another language that people generally consider as "dying", probably way more so than Ruby is) is used by a lot small companies. Would be interesting to see OP's data, but instead of amount of jobs it's amount of unique companies that offer these jobs to see if I'm correct in that assumption.

[Trasmatta]

This anecdotal, but I see a lot of small companies and startups still picking Rails.