Just adding my tuppenceworth, should anyone from Apple even be reading...
I also dislike iTunes 11 a lot and would prefer to revert back to my previous install. The fact that so many features are missing and there is no easy 'officlal' way to revert back without the risk of it all falling apart and throwing up errors speaks volumes about Apple and its software, mindset and attitude to customers now.
With this update I have now lost trust in Apple for good and I have now switched off all automatic updates to prevent any further nasty surprises in the future. I'll make sure to delay any upgrades until I have read about them properly in advance. I've always had that policy with my iPhone and versions of iOS, more fool me for having made this mistake in the first place with this software. But you just don't expect an 'upgrade' to rip out features you've become accustomed to. All the more galling to then read marketing guff about 'best ever' - mehhh.
But I suspect this is the beggining of the end for my relationship with Apple. I've read comments in other threads about how fellow users now use Apple because it is the lesser of two evils rather than because of its strengths - yep, I guess I'd say I'm about there now.