Another iTunes, another toolkit

What lessons should developers take from Apple's Human Interface Guidelines if the company that writes them cannot even adhere to them?

Amid all the fuss over the latest iTunes release, the new look of the application has not attracted much attention. This creation is the latest addition to Apple's ever expanding stable of UI toolkits -- we began with Aqua, then received Brushed Metal, Tiger gave us Unified and now we have iTunes 7.

Trying new looks for certain apps is not a big issue in and of itself (how many interfaces has Office on Windows been through?) except that it comes from a company that has created a set of Human Interface Guidelines that are widely regarded as the final word in interface design. Many application interfaces have been influenced by the guidelines regardless of platform.

Looking at the new UI, I couldn't help but wonder: where's the consistency? From Apple's Human Interface Guidelines:

"Consistency in the interface allows users to transfer their knowledge and skills from one application to another. Use the standard elements of the Aqua interface to ensure consistency within your application and to benefit from consistency across applications."

Am I crazy, or has the company completely ignored its own guidelines with iTunes 7?

Purple scroll bars? What was so bad about Aqua that they needed to change from lickable to boysenberry?

Not even the iTunes logo has escaped -- green obviously isn't good enough anymore and the Aqua blue finds its last refuge in the quaver.

What do you think? Is this another case of do as I say, not as I do?

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