Instead of answering OP's question, most posters seem to be saying "learn language X because it is my favorite language and the best programming language ever!" Completely unhelpful, although not entirely unexpected.
If you want to learn a language with a strong developer community and is well suited to building web applications, either Ruby or Python would be good. Personally, I prefer Python because I find the syntax to be clearer and easier to understand, but that's just my preference.
For the most part, the specific language isn't that much of a problem. Good programmers generally know more than one language and can learn a new one fairly quickly. Therefore, you shouldn't limit your hiring to people who are highly experienced with one particular language.
If you want to learn a language with a strong developer community and is well suited to building web applications, either Ruby or Python would be good. Personally, I prefer Python because I find the syntax to be clearer and easier to understand, but that's just my preference.
For the most part, the specific language isn't that much of a problem. Good programmers generally know more than one language and can learn a new one fairly quickly. Therefore, you shouldn't limit your hiring to people who are highly experienced with one particular language.