Much has been polished and much had to be redone, thus some things have been changed -- some compromises here as Windows 7 shares even more resources between different parts of the theme. So expect some details to be lost (like the etched look on the group sorting headers -- Windows 7 ignores the property and only allows a 1px height for the seperator), or the unique "New Application" button state for the Start Menu (that image is shared and grossly distorted in another area), amongst other things.