It seems a few sites saw this, but no one is quite sure when the update happened. That's probably because most of us don't go to Google's homepage for a search anymore–we just use the little search bar on the top-right.
One addition is those little icons at the bottom that let you select between things like Restaurants, Coffee and Bars. You can fill in a search term and then hit one of the icons, or just hit the icon to find restaurants or whatever in your area.
The map now floats on the top half of the screen as well. This means you can scroll through results while the map remains onscreen. Again, we're not totally sure when this update happened, but there are some interesting changes to the mobile site.