I personally don’t use genre to browse my music collection. I find it too difficult to pin a label on a lot of music these days; I would just end up stringing adjectives. iTunes 8.0 defaults to showing genre in the list view and does not allow you to change this from within the app itself. Here is a quick fix for this:
Open Terminal and type:
defaults write com.apple.itunes show-genre-when-browsing -bool FALSE
Then close and reopen iTunes and voila, genre is gone form the list view.
To put genres back, type:
defaults write com.apple.itunes show-genre-when-browsing -bool TRUE
Your iTunes browser will now look like this: