I haven't done a point-by-point comparison of the two, and, given the breadth and depth of features in both products, that would a heroic endeavor. I think, though, that when selecting a product as advanced as Microsoft Office and OpenOffice.org (Ooo) or StarOffice, it's not really a feature race, each product as a whole up against the other.
Many people have expressed, in one way or another, that most users only use 5-10% of the features in any given piece of software. So it's all up to you and what you really need. If you make extensive use of the document editing and tracking features, then either product will probably work for you. If you love OpenOffice.org's XML file format and the fact that you can unzip any OOo document and see and edit the source, then Microsoft is not going to do it for you. If you can't live without Microsoft Word's format painter tool, then you might not choose to go with OpenOffice.org.
So, I can't say how they compare because what's important about the comparison is very much an individual situation. If OpenOffice.org has what you need to do your job, then it really doesn't matter what features are in Microsoft Office.
This was first published in October 2003