I find Java to be perfectly reasonable (if not great) for some classes of web based applications. I mean, I wouldn't use Java for a generic company website that was mostly static HTML with no interactivity. But for a web based application that requires talking to databases, pushing messages onto a message queue, consuming web services, etc., I like it. Note that I'm not saying it's perfect, but that's half the point of what I was saying above. A language doesn't need to be perfect, it just has to be "good enough" AND meet a few other pragmatic criteria: availability of libraries, documentation, compilation speed, whatever it might be.

That said, Java also strikes me as a good choice for things like text mining, machine learning, data mining, etc. It also fits well where there's an emphasis on integrations with other systems, but that is, again, partly down to the availability of libraries. And just based on it's popularity for such applications, I think it's safe to say that many people find Java a good fit for building things like database engines, message queueing servers, etc.