That's what I want to do... change my genre to something that makes sense. If I'm in a Ska mood, I want to be able to listen to all my Ska songs, etc. I just tried renaming all my genres and then restarting iTunes before I played anything, and it didn't work. I changed The Aquabats from "Other" to "Ska", restarted, and then played the song. Immediately upon playing the song, it changed back to "Other." I've even uninstalled iTunes and reinstalled.
I have a brand new 14" iBook G4 running 10.3.3 with iTunes 4.2 (the newest one that showed up in software update yesterday after I uninstalled). I can't for the life of me understand why it's doing this.
[Edit] I forgot to mention where I get my songs from... I get a lot of them from CD's that I buy and some of them from... other places. I've never had this problem before though. When I had all of my songs on my PC I would change ID3 tags all the time in MusicMatch, but iTunes just won't have it. Oh, and it doesn't let me change anything else either. I have a Maroon 5 song that it won't let me change the artist to "Maroon 5" (without spaces). When I play the song, it adds like, 5 spaces after the artist name. Which when listed in the artists section, displays "Maroon 5" and "Maroon 5 ". I can't change Album titles without it resetting, Genres, Artist Names, or anything. It's irritating.