Having been a bicyclist in a hilly section of CT, a driver in the same area, and now a resident of NYC, I have been on both sides of the argument. From my bicycling experience, 99 times out of 100, a driver who would be angry at me for slowly making my way up a hill was angry because I was an inconvenience to their expected rate of travel. It was a response akin to having to stay behind farm equipment moving down the road.
Therein lies where I think the largest issue is. Amanda is totally right in seeing added issues with bikers on inclines and winding roads, but incorrectly demonizes the biker for this. A car driving down that same road also creates a risk and inconvenience. As would a pedestrian, animal, tractor, bad weather, and any number of other factors. At least in the states I lived in, the driver is always the one legally responsible to adjust driving habits to fit the conditions of the road. If that means coming around a blind turn, slowing down should absolutely happen, even if it means dropping well below speed limit. Sure, you will occasionally deal with a cyclist that has no sense in exercising extra caution in areas of lower visibility, but that is the exception.
The bicyclist represents a deviation from the norm and the comfortable for a driver, but that in no way lessens their rights.