Originally Posted by
David Bierbaum
I think Google gets all it's bicycle-related information from Rails-to-Trails Conservancy. Aside from the link in the "bicycling is in beta" blurb, when you get bicycle related directions on the map, I don't know of any method. I don't know of ANY "easy" method for interacting with google on anything, including changing my own profile and settings...

That is probably one source of many that they data mine.
I don't bother reporting or recommending routes unless there is something that is totally off from the map- like the road has a one or two block break. The reason why I don't make recommendations is that I'm cognizant of the fact that I'm not the strongest, most confident rider... but I'm not the weakest, paranoid rider, either. The routes I use match my comfort zone