UPDATED: De-Genre v3.0
Macworld's Chris Breen mentioned De-Genre in his recent column and it occurred to me that I should freshen that one up.
De-Genre v3.0 re-assigns the Library tracks of selected Genres to another Genre so that the originaland consequently un-assignedGenres disappear from iTunes' Genre pop-up list. This latest version runs as universal binary and includes the aforementioned freshening-up of code.