I agree with the fact that assholes are assholes whatever their means of transportation is. What pisses me off about some cyclists though, is that "I'm better than you because I don't pollute" attitude, at least we get that a lot here... My local council even made little paper tags to attach to your bike with "I don't pollute" written on it.
And those are the worst of them all, they're usually the ones that cut in front of you without signalling, that cross the road without making sure you have enough room to stop for them, or that dash in the middle of roundabouts without giving way to anyone, when there are cycle crossings all around it.
I do cycle from time to time, and following the rules gets me from A to B without anyone raging at me, or trying to kill me, while I risked several rear end collisions, while driving, because of cyclists that thought the road belongs to them.