Apple released Mac OS X v. 10.4.9 today -- a free update to the Tiger OS.
If you're using Illustrator CS2 on an Intel-based Mac, you've no doubt experienced grief, much of which has been noted in the comments of this post.
If so, make sure you download and install 10.4.9. According to my own personal tests on an Intel-based MacBook Pro, upgrading to 10.4.9 fixes the Pathfinder crash issue and also makes all of my zeros appear correct (not as -0).
I have no idea if 10.4.9 introduce any other issues at this time. But at least we have something to keep us sane until CS3 comes rolling around...