Except that the vast majority of features will never be used/needed by the vast majority of users..I really want OpenOffice / LibreOffice to succeed, but MS Office just has a much stronger piece of software. I couldn't recommend Open/LibreOffice to anyone right now, unless they were really skint.
I use MS Office at work and OO at home. All I do with MS Office at work, I could do with OO as well. Sure, some features are awesome, but most people won't use them
So for all those, OpenOffice (or LibreOffice if it takes off) is a perfectly valid choice