In Media Center 13 you can use the new views wizard to create a "view" for each genre that you want to be unique. Then you would choose which one to browse by picking that view in the tree, rather than picking a genre in a [Genre] pane of a regular view.
To do this:
1. Right click on the big Audio button at the top of the tree, and click on "Add library view"
2. In the advanced section of the wizard click on "edit search rules" and select the genre(s) that you want for that view
3. Add categories relevant to that genre in the "top list" section, and choose between regular panes view or the slightly better looking thumbnails view.
Voila! You might not be able to browse all your music on one convenient view, but once you psychologically get out of that way of thinking, and build perfect views for your classical, jazz, electronic, movies, tv, home video etc. you'll never look back. iTunes etc suck so bad exactly because they show you everything you've got all at once, and you end up playing something near the top of the list cos it's just too much effort to browse the whole thing.
The above method is pretty much the same for MC12, except the sorting options are in a separate place.
