I guess that you and I had different interpretations of the Arc challenge. I thought it was intended to demonstrate how easy it is to implement multi-page flows

I guess that you and I had different interpretations of the Arc challenge. I thought it was intended to demonstrate how easy it is to implement multi-page flows in Arc by binding closures to links and forms. I didn't think it was intended to convince people that Arc is a good general purpose language because its scope was so narrow (if the challenge were to build a search engine or an image editing tool, it would have been a different story). By the way, although I didn't expect people to extrapolate from the Erlang challenge that Erlang is a good general purpose too, I do think that it is, at least for building backends for a wide range of applications. I wrote a followup on my blog to the Erlang challenge where I listed some of them.