methods and DOM methods that you SHOULD be able to use but usually can’t because you have to support browser X (being, of course, IE). HTML5 also has newer tags, micro formats, and such, but that hasn’t been something I’ve really benefited from so much. I’m not building a website. I’m building an application. And those have different needs. I’m excited to use some of the other new features such as the client-side storage and database for speed and offline support.