I had my doubts about Ruby too, but we built the entire backend of our iPhone app (http://loqly.me) on ROR and our website is going to be entirely on ROR too. The amount of time it saves you as compared to any other language is nothing short of mind blowing. Of course I am just sharing my 2 cents since you asked. Others could have a different experience. But we started out with php and 2 months down the line changed over to ROR and boy were we glad we switched!