When I first learned to use jQuery, I went hog-wild, running circles around fellow devs who didn't use it. I got so into JS, that I started writing more logic in the client, because I could, and because JS, with it's loose typing and object notation was just a fast place to write code.
Now, two years later, I've embarked on a large project, an HMI in an industrial sector, and I of course made heavy use of jQuery. After 4000 LOC, the program needed some serious re-factoring in order to handle the next level of complexity.
To handle the complex demands of the application, I decided to use the Closure Compiler, which is great! The only problem is, that now, I'm writing typed code, in a non-typed language, and there's not much to really like about the language, besides the fact it's on all web browsers and has a ton of third-party support.
I guess my point is: I think tools like Closure Compiler and others which produce "compiled Javascript" are the future, if anything is. Maybe we'll see Python, or Java get JS like support in the browser, but if I could talk to the me from two years ago, I'd tell him: "Start using the Closure Compiler, and use less jQuery."