Lots of new stuff in the Office SP2, dont forgett to update your clients also!
* Two new STSADM commands, one to check compability with vNext of Sharepoint and one to analyze ECM sites for errors.
* Lots of improvements to rendering of webparts, almost everything works in Firefox now.
* Better performance when using page varations
* Forms authentication for SPD
And lots lots more.. read the full details here.
Download WSS 3.0 SP 2: http://www.microsoft.com/downloads/details.aspx?FamilyID=79bada82-c13f-44c1-bdc1-d0447337051b&DisplayLang=en
Download MOSS 2007 SP 2: http://www.microsoft.com/downloads/details.aspx?displaylang=en&FamilyID=b7816d90-5fc6-4347-89b0-a80deb27a082
Download Office Suite 2007 SP2: http://www.microsoft.com/downloads/details.aspx?FamilyID=b444bf18-79ea-46c6-8a81-9db49b4ab6e5&DisplayLang=en