I have received two reports over the past couple of days of some unusual behavior that occurs with iTunes 9.2.1 and some AppleScripts. After running a script that changes the track name tag, the track's Genre tag is replaced with a number in parentheses, eg, "(10)". In such cases, it appears that this is a number representing the specific Genre, such that Rock = 30, Jazz = 10, and so on. Like this:
Each report involved a different script which until now presented no problems. Experience suggests that this is not an issue with the scripts (since nothing about the script has changed) but with iTunes.
I have not seen this behavior myself, but I have not yet done any rigorous testing. Since I have only received two reports at this point my guess is that this may be a problem with something else and iTunes; a misconfigured plug-in or background app. But that may be wishful thinking and the problem may indeed just belong to iTunes.
If you have seen any behavior like this please let me know as soon as you can. I'd like as much information as possible before I test and eventually report this to Apple.
[UPDATE: see here for the fix.]