my 2 cents:
Ruby on Rails is quite nice.
But it's frustrating to try to compare it to other languages because its really a Framework on top of a language.
Comparing Ruby On Rails to PHP is not really fair - there are TONS of frameworks for PHP that are trying to provide the same functionality as Rails, and very few people ever compare them to Ruby on Rails.
In some sense you see this kind of debate all the time, where people say they love product X, when it's really nothing to do with product X that they love, but rather some auxiliary feature of X.
I'm not particularly thrilled with Ruby syntax or design decisions - but i fully recognize the speed that you can develop safe web applications with Rails. It is a highly structured framework that really forces you into a very specific way of designing a tool - which is not common in language frameworks. I can't help but feel that some of the love for Rails is due to this well thought out and highly structured system which guides you through designing your service. It's almost like you are modifying an existing "tool" rather than using a language.
So, if Ruby on Rails matches well with the tool you want to create, it could definitely save you some time and pain and help you create something really nice. I'm just reluctant to say it has much to do with Ruby the language..