Detect whether Office is 32bit or 64bit via the registry

Question

Now that Office also comes in a 64bit install, where in the registry do you find out if the version of Office installed is 32bit or 64bit?

Answer 1

I have win 7 64 bit + Excel 2010 32 bit. The registry is HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\14.0\Registration{90140000-002A-0000-1000-0000000FF1CE}

So this can tell bitness of OS, not bitness of Office