Zotero have released a compiled version of Zotero Everywhere for experimental use (version 2.1a2). So far, it's a good start but you are not going to see much more functionality if you are already a Firefox devotee.
I have not tried it on more than one system, but it allows you to share your existing 2.1b4 database without upgrading, so you can try it out without having to reinstall Zotero for Firefox (just disable it before running standalone Zotero). This worked fine on my system. However, the plug-in for Word 2007 was not working on my particular system, although I did remove my existing plug-in before running so that it could install the new version. It also increases the memory overhead at this stage, but not in a detrimental way to a computer with plenty of memory.
In summary, take it out for a walk. Show it your database and let it root around. Make a backup first. It ain't no beauty, but it's progress. Well done to the team and keep trucking. In the wise words of Iarnród Éireann, "We're not there yet, but we're getting there".