The Modern Language Association has released the 8th edition of its MLA Style Manual (there is a link to purchase the book below). Their website has a breakdown of what is new in the eight edition. Purdue Online Writing Lab (OWL) also has a page on what is new in the eighth edition. (Their main MLA page is here.) Chegg has updated its online guide to MLA to the eighth edition as well.
Here are some other posts on MLA citation.