I have seen some pretty shitty games made with javascript.

As a language, it has been used for... well, simple scripting and webpage stuff.

Not any more. With Chrome and Safari boosting the speed of the language, developers have begun to create some amazing new projects.

For example... A NES emulator!

http://benfirshman.com/projects/jsnes/

Java and Javascript are two totally separate languages. While similarly named, they have almost nothing in common.