I just installed KitKat on my Nexus 7 and I'm discovering the new look & feel. The new colors are a very very strange choice. You hardly see your selections now. And I discovered my first KitKat bug: the fast scroller of listviews has been completely rewritten. Unfortunately, it doesn't appear any longer on my device.
Did you get the OTA or you sideloaded KitKat?, there are some horror stories about the upgrade that ranges from bricking the device to some other weird stuff.
Google is holding back the upgrade since started to push bug fixes, I'm still waiting for KitKat on my Nexus 7.
Yes, the white accent that makes the holo light theme not very usable. And I see they forgot to apply these new colors here and there. You can still find parts with the holo blue.