I do not like the new stacked layout of the main navigation bar. On a 13" laptop screen the layout is way too crowded already. This takes up valuable vertical real estate without any real benefit.
Take a look at my deals screen! (Yes, I know I can turn off the deals summary section.) But, do you see how crowded this is getting!? This is with a web browser maximized to go from just under the Mac top menu to the top of the Mac system doc.