I upgraded my Mac to Office 2011 just after it was launched, and have been disappointed in many ways. My main concern is when I receive files (mainly Word and Excel) I often receive a warning, and I am unable to open the file in Word or Excel. I can open with Numbers or PAges, or even in preview mode, but this doesn't help when I need to copy (and paste) documents into reports. Very frustrating. The message that is shown is: filenamexxx.doc uses a file type that is blocked from opening in this version. To help secure your computer, some file types are blocked from opening when you double-click the file or drag the file to the Microsoft Word icon. If you trust that the file is secure, you can open the file by clicking open on the file menu.
You would think that is an easy option, except that it doesn't work. This also happens on some files that were written in the older Office version, so it not only stops you receiving files in older versions of Office programmes, it also stops you opening your own saved files that were created in an older version. Is this a cynical ploy by MS to get the world to upgrade?
my advice, don't upgrade, save yourself some money and a lot of bother