Well, within the past year, Detroit's gotten 45-degree images on Google Maps, updated Street View images taken between June 2011 and this past July and now, just tonight, I was randomly on Google Earth, so I turned the "3D Buildings" layer on and I noticed that my whole block was 3D! So I browsed around and noticed that the entire city east of Hubbell Street, both enclaves, all Grosse Pointes [[including Harper Woods), the northern quarter of Windsor and everything in a strip that extends from the Detroit River westward to halfway between downtown Ypsilanti and Willow Run Airport and from just south of Palmer Road and the Henry Ford southward to Pennsylvania Road [[as well as tiny silvers of Oakland and Macomb Counties along 8 Mile Road) was wholly 3D now. Every single building, bridge and tree [[and yes, even every billboard) within the mentioned regions is now rendered in 3D.

For example, if you zoom in close enough at Woodward and Jefferson, even the Spirit of Detroit, Joe Louis' fist and the People Mover track are in 3D. It appears that the 3D images were taken at the exact same time as the 45-degree images, since even the 2012 Wyandotte Street Art Fair's in 3D.

NOTE: Before you turn that layer on and pretend Detroit never declined, please compare those images with any of the aerial images on this site:
http://www.clas.wayne.edu/photos/ap_index.htm