Autodesk has never published a public-facing Revit Roadmap, until recently!
Here is the link to the Revit Roadmaps.
Autodesk has advised they will post updates periodically, and they want your feedback! Let them know what you think and want to see. If there are specific areas of interest, you can submit requests through Revit Ideas - http://www.autodesk.com/RevitIdeas
I wonder what roadmap functionality will show up in the next release?