Anyway, I'm not arguing that Java is the most active in this regard, just that this particular criticism - of all the ones one could level - is, in my humble opinion, relatively weak.
True development is happening within the Haskell community, for instance, where they're taking concepts from various fields of mathematics and applying them to software development in ways that haven't really been done before.
Most Java-based projects are merely reimplementing something that somebody else has already done, or they're making minor, incremental improvements to a well-aged piece of software.
It would be interesting to graph the average ages of the users of the popular languages; youth being a proxy for the (perceived) current best thing. When you're starting out, why wouldn't you choose that?
> in languages other than Java - they have more interesting
> tools (eg. Sinatra), and more interesting energy in the
> community, because they attract those crazy, eager,
> young, passionate, enthusiastic early adopters.
Of all the comparisons I've heard, this is one I'd say I'm dubious about. There is still a LOT of activity in the Java space, and lots of cool and interesting tools and libraries continue to be written in Java.
Off the top of my head, I'd mention Lucene, Hadoop, Weka, Mahout, Tika, HornetQ, UIMA, GATE, Camel, Jackrabbit, DERI Pipes, etc., etc. This isn't too say that other languages don't also have lots of activity in tools and libraries and frameworks, but I think Java is still in pretty solid shape in this regard.