Java

I used Java quite a bit while I was working at Clearwire, mostly to create web services for use with a PHP front end.

Personally, I've never been a huge fan. While it might have been my companies policies and architectures, I found Java EE to be extremely slow to develop in, owing to layer upon layer of abstraction (often aka obfuscation) and rather long build processes.

While I recognize that it has value in situations where you needed threaded processes, I'd much prefer to use PHP for the majority of projects I deal with.