Jumping from "a few" to comparing against C and Java is quite a leap. The simple fact is that Heroku alone had over 60,000 apps 2 years ago, and based on other statistics I think it's safe to say that Rails is a tool used by millions of programmers.

http://trends.builtwith.com/framework/Ruby-on-Rails

You're entitled to not like 37 Signals or think they give poor advice, but you shouldn't downplay their contribution so much.