They will use the Skylake processor. The wait has been long but personally I don't see the point in regular small updates, I'd rather they brought out replacements every couple of years with a significant change. I like eh idea of the touch panel strip along the top of the keyboard, apparently it will change depending on what you are doing. This would be very useful for LightRoom and other apps that use many different options, giving quick access to various tools and shortcuts. I'm not sure they could drop USB completely, too many people have a need for a USB connector just now. The SD card slot may well be useful, but it's more useful for extra storage than as a standard card reader in my opinion. As for the colour I really don't know, but they do like them to look premium, I think they are trying to differentiate the range more with the MacBook, the Air will only come in the larger size rather than the smaller version although I used to have one of the 11" Airs and found it perfect for general use. I have always put a skin on Apple laptops, so I would do again and not really care what the colour wasn't underneath.
I just wish they still came with floppy drives, I miss those days!