It's extremely well-designed and battle-hardened code, and it recently had a major release.
Most of the non-enterprise customers pay because we want to support Mike Perham, not because we need paid-tier features.
Beanstalkd is simple, scales, and is platform agnostic.
At scale, simple wins.
I don't think anyone here suggested that Beanstalkd is bad or should not be used, if it fits your use case like a glove.
Speed-wise, let's not forget that Redis is also written in C.
Bigger picture, folks outside of the Rails community love to sidestep the simple fact that something like 75% of the total value created by YC-backed companies was created by the subset who built with Rails.
Clearly, we're connecting the dots in a way others are not.