AMC3  I have the same MacBook set-up and also use NeoOffice and OpenOffice. Virtually all docs of either of those two apps open and save just fine in each other, and both seem to offer better value that MS Office for Mac. The reason I use both is certain feature sets available in each. Both to me are now pretty much on par, but I find that OpenOffice gets more use because of all the available extensions for it and the fact as each are updated via a pop-up at launch it gives you the option to update the extensions. I hope both continue their development. My 2 cents.  
(Version 3.1)