That's a realy old screenshot. GNOME 3 doesn't look like that anymore[1].
[1]https://people.gnome.org/~engagement/screenshots/gnome-3-24-...
[1]https://people.gnome.org/~engagement/screenshots/gnome-3-24-...
Most GNOME apps look great because they titlebar is actually a toolbar, but I spend most of my time in portable third-party apps which have large, empty titlebars. This is the one thing I immediately envy when I see a Unity screenshot.