Google 1 : 0 Open Street Map
Though I must say that to large extent it is also poorly programmed, for example the zooming feature using mousewheel is supported by OSM as well, just that they probably didn't include it in the code. Most of the stuff probably could be replicated and brought to similar state as it was when using Google, however, one thing that cannot be overcome is how up-to-date the maps are and again, no matter how much you like or dislike Google, one has to admit they have no competitor as far as map coverage goes.