This. Also it's inconsistent with the bar at the top of the Gmail interface. Perhaps this will be rectified/consolidated going forward. Overall it seems like a strange choice for the company that popularized the clean white interface.
If there are things you don't like, the thing to do is send feedback. I can't stress this enough. As it says in the blog post, the changes are coming across months, not days, so there is always time to change course on something given enough feedback.
