Reference counting in general has been an interest of mine since even when I'm writing server-side software it's usually pathological-case latency rather than raw throughput that really matters.
It's a pity that it's mostly C++ (smart pointers) and Obj-C (ARC) that have access to this.
( I say this realizing Python is hybridized. )
Edit: Most of my hesitations regarding using the JVM have to do with how incredibly finicky tuning it can be.
Reference counting comes with a huge toll on interoperability. Forget one Py_INCREF(Py_None) in a tight loop, and you're up to a segfault in a place very, very far away.
I'd be interested to hear what a ruby core dev has to say about this, aren't they working on an embedded version of the MRI? Otherwise, I'm not in favor of not being able to manage memory, some might think its a pain but when you have no memory, then you want to be able to crunch every byte when you need it. I think it could be interesting though, ruby is a very HL abstracted language, and if it gave you enough control it could make writing embedded programs a lot easier.
It's a pity that it's mostly C++ (smart pointers) and Obj-C (ARC) that have access to this.
( I say this realizing Python is hybridized. )
Edit: Most of my hesitations regarding using the JVM have to do with how incredibly finicky tuning it can be.