I like the new icon better than the old one, however, I'm sure they could have made it even better. We're Apple people, so it's totally okay for us to talk about something like an icon. We admit that it's ridiculous and we're fine with it.
I think the shade of blue they used doesn't go well with the Finder, Mail, and Safari icons. It's a deeper blue, closer to the Photoshop blue rather than the Skype blue, if you get my point.
The rounded, glass icon is very classical Mac-like, there is nothing new about it. It's very simple, and I think it doesn't really represent iTunes much. It could be any random music button on any website. However, I still like it more than the badly-balanced CD icon.
Have a look at the orange music note icon on the iPod Touch. It's pretty plain and boring too, but it's really simple and that's the only point. It's a music note, it's round, it's shiny and blue. It can't get more Apple than this.
Now the thing is that Apple usually likes to have a retro-styled object represent the application:
Stamp for Mail
Compass for Safari
Clapper for Final Cut Pro
Ink bottle for Pages
Etc...
So maybe a Vinyl icon for iTunes would have been better. The CD isn't retro enough, but maybe a gramophone or a black Vinyl disk would be cool.
I like the new gray iTunes UI though, the only strange thing in my opinion is the volume slider's button: it wants to look like the iPod Shuffle's brushed metal buttons, but it instead looks weird, since it doesn't look shiny. maybe a more classical grey rounded aluminum button would be fine here.
But seriously, only Mac users talk about stuff like this: on Windows, you would have an endless list of ugly UI and icon choices, so it's not even worth starting.