[trileansoftware]

Yes you can report problems with the road network and people update GMaps manually. And up until a couple of years ago users could do it themselves, but they took it down for some reason.

Changes to other types of places can still be done manually by GMaps users themselves, and other users can evaluate that, and I guess if it's a "controversial" (low rep user did the change or people voted against it) a Google employee evaluates it. And if you're beyond certain level as a GMaps user you can get most changes published immediately.