This is one of the things that drives me nuts about the IT sector: for way too many people, things aren't real unless they've been blessed by the "right" analysts:

What if all of us enterprisey folks were wrong to think that Ruby on Rails isn't ready for the enterprise and we decided to ignore lack of industry analyst coverage, lack of any quantity of knowledge in large consulting firms or even lack of a single hint that there is a single Fortune 100 enterprise whose primary business model isn't technology and how they have used it to develop a mission-critical enterprise application?

Would it be so hard to find a non-critical need, and try a pilot project? Why take someone else's word for the "enterprise readiness" of a solution when you could learn the truth for yourself?