There are a lot of cities with amazing 3D building coverage, but one you may not have seen yet is Istanbul, Turkey. Thanks in large part to the work of a company called 3DLocationEarth, the 3D buildings in Istanbul look amazing!
Another great example is from a little cafe; notice the detailed 3D tables and chairs outside.
3DLocationEarth has over 5,000 models in the Google 3D Warehouse, though the Warehouse will only show you 2,500 of them. You can view them here. You can learn more about them on their Google profile page.
To check out these buildings in Istanbul for yourself, you can use this KML file to fly there and explore them.