I too find Windows 8 smoother and faster than Windows 7 x64 for my audio work. The Start Screen doesn't bother me that much as I'm rarely seeing it but the Charm Bar drives me nuts. I hate that thing. As for Bing being forced on us, I'm not fond of that idea but considering all the privacy issues and security problems Google seems to be having lately, especially with Android, maybe Bing isn't so bad.
Google, with Google Now and it's integration into smart phones is getting downright creepy IMHO. It can be mostly turned off though.
Anyway, overall Windows 8 has been fine for me.