I am mentoring a startup that chose RoR because the founding team liked it. However, they are unable to find local talent sufficiently interested in an entrepreneurial venture in the Houston area. Sure, one can find remote resources, but for startups I am a strong believer that the technical co-founder should be in same city as the founder. It is definitely OK and probably even better if rest of the team are at offshore or remote sites.
Availability of talent is a critical component of technology choice!