Great read - I wish he had put in the Canadian equivalent of it because he missed one other aspect of it: the government taxes.
For example, in Canada, we're today at 90 cents a litre - but in truth, about 40% of that is taxes. Here's another site that explains it in more details. As the index shows , 98 cents a litre in Ottawa is really 66.9 cents when you take away the taxes.
So when we compare ourselves to the US, we always say when they pay far less than we do in Canada (using Markus' example, Canada we would be paying about $3.75 a gallon, far closer to the European example)
But then Markus actually then puts it into perspective - compare how far it is for 100KM and then look at the changes across the board.
Don't single out the US - everyone in North America is getting the short end of the stick when it comes to rising gas prices. (oh, except the Canadian government who makes money when the price goes up)