As someone who has programmed in at least 15 different languages and taught 6 of these to students, I havn't found a more productive tool and environment to teach and work with than Python. It is possible if I knew Ruby as well as Python I would feel the same about Ruby. I doubt Ruby is as mature as Python, though it is probably not far behind.

Python is excellent for teaching programming to beginners and more advanced students, for making the logic of applications of moderate size readable and maintainable and for making very large projects feasible. It is getting into a growing range of environments including web applications, embedded systems, GUI applications and mobile phones. I can think of very good reasons for Sun to support it, but they can't afford to be a one language company. Java will be used by large banks and finance houses for some time to come and 'C' will continue be used for high performance operating systems and system tools, incuding Java and Python compilers and virtual machines.

An interesting trend exemplified by Jython and IronPython is for one language to be compiled into the bytecode of another, e.g. so that a Python application can access .NET or Java library code.

One of verbose loudmouth genius Steve Yegge's big predictions for the next few years was that Java would cease to be the most popular language on the JVM. Possibly Sun is seening the same likelyhood and trying to make sure that JVM versions of languages like Python and Ruby are stronger than their .net runtime alternatives.

The JVM is one of the most sophisticated cross-platform virtual machines around, so there could well be major benefits for scripting languages able to run effectively in that environment.

I didn't mean to imply that Python will disappear, just that Sun's support can be fickle. Who now remembers TeamWare, the source revision control system they once promoted, or that they once sold the Unify database? But they were closed-source systems, open-source goes on with or without corporate backing, so Tcl lives on long after SunScript was dumped, and no doubt Python will too.