Still issues in Berlin, as well
After the iOS 7 update, Maps looks a bit better (especially when it comes to separating major roads from the rest of the pack), but the data still remains out of date. (At least over here in Germany considering Apple's traditional US focus, I wouldn't be surpised if the American maps were of better quality.)
Berlin's old Tempelhof Airport has been closed for several years (i.e. before Maps ever came out) and is now a rather cool public park with runways still intact. Still, Maps insists on labeling the area as an airport. Considering how many iOS users there are in Berlin, I'm sure Apple must have gotten countless reports over the last year (several from me), but they don't seem to be top priority, apparently.
Don't even get me started on the business data in my neighborhood: Many listed businesses are either at the wrong location or they closed years ago. (Yes, I reported them for a while, at least bit all the errors are still there. Since none of the reports ever seemed to have any effect, I've pretty much given up on trying to improve Maps data over here.)
On the bright side: The local sat images are quite current, and the 3D buildings look stunning. Maps is my go-to app, if I want to impress people with eye candy or give them a visual idea of my neighborhood. For daily use, though, I fire up Google Maps.