Essentially, the add-on allows you to view these MS Office files the same way you are used to viewing PDF files in your browser rather than in an external program like Adobe Acrobat. While some of the add-on reviewers seem to have issues opening every file type the Chrome Office Viewer is supposed to be compatible with, it is important to remember that the product is still in Beta and is not, yet, entirely perfected.
Download – Chrome Office Viewer add-on