AppleScript Changes in iTunes 5.0.1
iTunes 5.0.1 was released on September 20, 2005. It contains "several stability improvements" over v5.0.
I've only detected one specific AppleScript fix so far. The ability to set the description tag via AppleScript has been fixed. This, along with category and long description are primarily used by podcasters. However, if you don't care about that, you can use description and category for your own information since these two tags can be viewed in the browser and used as Smart Playlist criteria. The long description tag is used by the iTMS and, probably, some podcasting software; it is not visible in iTunes.
More as it develops...