If you're missing Google's black navigation bar, there's a parameter that brings it back. If you add "?noj=1" or "?noj=0" to a Google search URL, you'll temporarily replace the app launcher with the black bar. Here's the "black bar" version of the Google homepage: http://www.google.com/?noj=1.
This doesn't change the interface permanently and it's not clear for how long it will work. The parameter also disables Google Instant and replaces it with the old Google Suggest.