That is certainly a problem. But there are very few language constructs in Python >= 2.6 that are missing in Python 2.5, and the really missing features (e.g, multiprocessing module) have better alternatives in the JVM, or are redundant. You lose some portability, but Jython 2.5 doesn't seem to be that limited in capabilities.

Anyways, YMMV. All I got to do once was set my Django application to run on Jython, and that was relatively painless.

While I'd agree Python 2.5 to 2.7 doesn't bring a swath of language features with it... it's a good sign of Jython's slowing/sluggish growth/development.

Personally, I want to use a language implementation that will be around and (well!) supported for many years.

None of you three mentioned Python 3.0 to 3.2.

That's because they don't matter to anyone.

It seems common that people don't upgrade to a breaking version of a programming language based on name or distro channel alone. Hence the slow uptake of Python 3 and Perl 6.