The future of web development looks a lot like this (Rails on Javascript on the JVM).

I’ve been spending a lot of time learning Javascript, and I’ve made no secret of the fact that I think it’s a better option for web development than Ruby (mainly because it means you only need to learn one language for both client and serverside programming) .

BTW, if you don’t already read Steve Yegge, go and catch up now. I think his Javascript 2 to bytecode compiler (I assume that what it is) is a great idea, too.

Also, JSC looks interesting.