I had the same issue as everyone here and I think I've FINALLY figured out a solution!
Go to c:/Program Files/Microsoft Office/Office 14
Right click on each program icon individually and unpin from BOTH your Taskbar and/or Start Menu. (e.g. EXCEL.EXE, MSACCESS.EXE, MSPUB.EXE, OUTLOOK.EXE, POWERPNT.EXE, WINWORD.EXE, etc.)
Then right click and select "Pin to Start Menu" (not to Taskbar).
Do this for each program you want to eventually make it onto your Taskbar.
Now go to Start and then for each program (that should now show in start menu with the actual Microsoft Office icon), right click and select "Pin to Taskbar".
You can then Remove each one from the Start Menu if you wish by right clicking again and selecting "Remove from this List".
Your icons should now be back to their original format.
I've rebooted my system several times so far and the icons have remained.
Hopefully this will work for everyone else as well!
Good Luck!!!