Signifying the application's complete re-write is a new logo for iOS Maps: it is basically a redesigned version of the current iOS Maps icon with a view of Apple's 1 Infinite Loop Campus, but redrawn with a new color scheme. Apple's replacement for Google Street View will likely also be an in-house solution. C3 Technologies worked on street view capability as shown in the image above.
The most important aspect of the new Maps application is a powerful new 3D mode. The 3D mode does not come enabled by default, but users simply need to click a 3D button that is conveniently and visibly stored in the app. Perhaps under the fold like the current traffic, pin, and map view buttons. This 3D mode is said to essentially be technology straight from C3 Technologies: beautiful, realistic graphics based on de-classified missile target algorithms.
You can learn more about C3's 3D mapping feature here. It's expected that Apple will introduce the new Maps application at WWDC 2012 in June.
Notably, the site also suggests that versions of iOS 6 are floating around Apple's labs and that there has been little improvement to the home screen and no Android-like widgets.