Due to the mandatory 'contribution' for Open Source NeoOffice, the Mac optimized version of OpenOffice.org, I have been testing LibreOffice for many months. At this point I can say:
Get it! I like it!
The current stable version is 3.4.4. Today there is also a new 3.5.0 beta 1with a long list of minor updates.
I'm using LibreOffice 3.4.4 with Mac OS X 10.7.2 Lion without the bombing that occurred in many early versions. It has all the features, and niggling annoyances, of OpenOffice. If you're into writing directly into, as well as editing inside a capable but free office suite, this is sweet. The output format is the OpenDocument world standard. But it is capable to doing all the major other format exports as well, including that mess of Microsoft formats. I've found RTF is still the best all around standard, even today, in order to deal with all the legacy word processor users out there.
NeoOffice: Donate if you like it, or compile it from source code yourself. But LibreOffice does a very nice job completely replacing it IMHO. And yes, LibreOffice would like your donation as well!
[What exactly is LibreOffice? It is a branch off the original OpenOffice Open Source project. It is now generally considered to be superior to the ongoing OpenOffice project, which has become bogged down in politics, corporate noise from Oracle and migration of volunteers over to the more ambitious LibreOffice Open Source project. Unlike NeoOffice, LibreOffice is offered in compiled form ready to use. Of the three current flavors of Open Office for Mac users, LibreOffice is consistently at the edge of the progress curve. Its problem in the past has been instability. However, I've found that problem to have largely been solved.]