Code is code - it's the concepts behind it that matter. If this is going to paying project then go PHP - it's what you know and you'll be able to get it done faster and probably with higher quality. If this is just a project for your own gratification then I suggest Ruby - or Node.js or Haskell or Erlang or 8086 Assembler or ... It doesn't matter. When you are your own client you do what you need to do to make you happy. Doing something because we busy bodies on HN think you should ultimately does nothing for my happiness or yours.