From the outside looking in the vast majority of people I know making web apps in ruby are doing so with rails. For better or for worse there is that full blow framework culture there that hasn't been replicated in PHP either due to fragmentation or the amount of functions built directly in the language.
True. I wouldn't say that it's because of the number of things built into the language though, it's more that Rubyists tend to care about software engineering, and so they'd rather do something the right way with full tooling than just throw up one page spaghetti scripts.
