The "none" bug I described yesterday turns out to be a bit more extensive: it's a "none/all" bug.
iTunes 8.2 introduces a bug whereby the the use of the none value with special kind and video kind, and the all value with song repeat in AppleScripts compiled in iTunes 8.1.1 and earlier will not work correctly in iTunes 8.2. I understand that Apple is aware of this situation and assume a fix will be forthcoming in a future version.
If you encounter an error caused by this bug, chances are you are running iTunes 8.2 and the script had been compiled and saved with an earlier version of iTunes.
The fix is to open the script in Script Editor, look for chevron-bound raw constants, and replace them with the appropriate bare-word value. For example, if you see «constant eSpKkSpN» change this to none. (I'm afraid I don't know what the raw constant for "all" is, but it would appear with a song repeat command; song repeat takes the values "off", "one", and "all"). Then re-save the script; it will compile referencing iTunes 8.2 aete and will work fine. Such recompiled scripts, however, will then not work with pre-iTunes 8.2.