I'm having a similar issue with one install of Revit 2012. Here is the process:
1: Create a floor (for instance).
2: Create something else, or press Escape a couple times.
3: Select the floor object.
4: The Modify ribbon tab should change to show the "Edit Boundary" button, but instead is still showing the tools for creating lines:

Whatever I do in Revit, the Modify tab shows the previous state, not the current tool I need. It affects all users on this machine. Ribbon has been reset via VBS script, Revit has been uninstalled/reinstalled, Quadro drivers have been changed, updated, rolledback, and Direct3D acceleration has been turned off and on. Nothing has gotten the Modify tab to work properly.
I can either cycle the ribbon state (from full to tabs, for instance) and the menu is then correct, albeit a different size. I can then keep cycling the menus to refresh the Modify tab, or I can Ctrl-left-click drag the tab to another position, and the correct menu appears.
Very frustrating and impacts productivity. Anyone else have this, or am I the only person on the planet? All other Autodesk apps work perfectly fine, the only issue is with Revit.
Jenni