Heh, it's always been like this in Apple-land.

I fondly remember Ars Technica's review of Mac OS X Developer Preview 3, back in February 2000, where John Siracusa roasts the "lickable" new Aqua UI that's a complete mess:

http://arstechnica.com/apple/2000/02/mac-os-x-dp3/

A good and honest critic is the artist's best friend, even it may sting for a moment.

Why? This is what betas are for.

Apple moves away from Aqua after more than a decade using it, and you're surprised designers have already started pouring over the details to see what's new?

You don't think Apple presents their visuals designs as nearly finished in these betas?