The issue is nobody knows the truth here. I think the more plausible scenario is that Google wanted something that Apple refused to give (e.g., advertising revenue, user data, etc), making it not so clear cut as "It's XX's fault!"
In recent weeks, I've seen the further claim Google was willing to license turn by turn but insisting on user location data for Latitude.
(There are no indications of a Google Maps app AFAIK but I also hope we will get one soon …)
Link: http://appleinsider.com/articles/12/09/20/rumor_of_google_ma...