Kickstarter, AirBnB, Github, Scribd, Bleacher Report, Hulu, Codeacademy, the 100+ startups that message me for interviewers every year, etc.

I was only making claims for rapid prototyping. I still contend for prototyping there is no better framework than Rails. From the start DHH designed Rails specifically for prototyping of web apps, and your custom prototyping infrastructure will sit very nicely on top.