There is a lot that factors in to that, such as the large amount of rural territory in the U.S. and the very old infrastructure in many places. Still, the U.S. is lagging, and may soon lose their spot as the country with the most connected as well, to China:
In terms of total broadband users, the US leads the pack with over 60 million broadband subscribers. But second-placed China is fast closing the gap. From 41 million broadband users a year ago, China now has more than 56 million and based on its current growth looks set to over-take America as the world's largest broadband market later this year.
The figures don't look well for other high-tech countries either, such as the U.K., who holds the spot of number 17 worldwide. South Korea, on the other hand, with a much newer infrastructure, is up there with Finland. According to the article, around 1.1 billion people have Internet access today. That's a pretty impressive figure for a technology that was in its infancy only a generation ago.