Most front-end developers already use some kind of build processes for their projects, even if the might not know or don't use the term for it: They concatenate files for production, minify JavaScript code to speed up page loading and convert Sass or Less files into CSS for the browser. Grunt helps to manage all these steps in one single location and orchestrate third party components.
Sweet. I still need to test this, but if this will automate my frontend build process I will be super pleased.