Is ArcGIS 10 SP2 worth installing?

I haven't found any new bugs in the types of things that I do and SP2 has fixed a number of critical ones for me which relate to computation geometry and working with geometry objects. For example, Errors in arcpy's Polygon class

So in short...you won't know what new bugs have been introduced until you do some of your regular work. I would suggest that you go through the NIM list of fixed bugs on the download site.

Here is a list of the issues addressed by Service Pack 2:

http://downloads2.esri.com/support/downloads/other_/ArcGIS-10sp2-issues.htm

It doesn't look like NIM067942 has been fixed in this service pack, but you can check the list to see which other items affect you.