The Autodesk wiki help site now has the Revit 2014 on it as well as some of the other programs. If you want to read the official what’s new, according to the help file, then check out the links below. I do like the way they have it broken down for BIM managers, Installation etc.
Since Autodesk went online with the help files years ago they are available once the software is available for download. If you don’t want to download you can still check out the What’s New for most programs.
http://wikihelp.autodesk.com/Revit/enu/2013/Help/00002-New_in_Revit_2013
With the new Building Design Suites there is also a suites workflow.
http://wikihelp.autodesk.com/Building_Design_Suite/enu/2013/Help/0153-Suites_W153