OoO 3.0 is available now. Check out what J.A. Watson had to say about it:
If you are still using Microsoft Office, you should really give OpenOffice a look. It can be installed on a system which already has MS Office without creating any problems, you simply tell it on installation not to take over as the default application for MS Office files. If you haven’t updated to MS Office 2007 yet, you’ll be pleasantly surprised to find that OpenOffice 3.0 is able to open MS Office 2007 documents with no problem and without a format converter – unlike Microsoft’s own pre-2007 Office versions.
Open Office is free. Some people like it and some people don’t. You can decide for yourself and download it here.