For everyone complaining "BUT WHAT ABOUT ALL THOSE GLOSSY SCREENS?!?!", this is exactly the same design as the Upper West Side (NY) Apple Store, which I worked at for just under a year. (The only difference is it's all on one floor.)
And yes, it was bright in the daytime. It was also friggin' beautiful.
Granted, our Genius Bar was downstairs, but the point still stands-- it would have been wonderful for us Genii to get some fresh light and air!
Apple has extensive experience with getting their heating/cooling costs under control. No one EVER felt the UWS store was too hot-- most people thought it was much too cold-- and it was rumored to have some kind of solar/photovoltaic cells in the roof to help with power. It also definitely has some kind of UV barrier that reflects certain kinds of light.
It's been working for them for almost two years-- certainly they've planned for California light, too.