If iTunes is crashing every time you edit ID3 tags, you need to remove all of your Visual plug-ins. Move all files out of ~/Library -> iTunes -> iTunes Plug-ins, and /Library -> iTunes -> iTunes Plug-ins -> Visual Plug-ins. Then quit and restart iTunes, and you should be able to edit ID3 tags now. If you want your visualizers back, then add them back in one by one, and quit and restart iTunes and verify that you can still edit tags.
I verified that the latest versions of Whitecap, G-Force and VolcanoKit don't cause this crash.
I hope this is useful; I had trouble finding a definitive solution on the web.
Mac OS X Hints
http://hints.macworld.com/article.php?story=20041203014328834