For me, the main difference comes from $$$/hr...yeah.. I code for living so mind as well picking the biggest $$$/hr
This is what I think so far.
Probably, Java and .NET is pretty close in pay but since there are more demands in Java... I'll assume Java gets paid better. For PHP, it doesn't seem lucrative but one can get a job with a college degree and it's a lot better then working at retailers. I know this is going to sound stupid but I just following where $$$ is..regardless how one is better or not. Honestly, the quality of the code comes from a programmer and not from the language. If one truly thinks an app is better because it's written in a specific language is probably not a bright person or just a fanboy of that language.