MediaPost via ExecutiveSummary.com: U.S. Internet Growth Rate Coming to an End?

My first column for MediaPost (via my ExecutiveSummary.com web site, as MediaPost didn't post the charts I assembled, so this is a bonus link). The introduction to my thesis:

Is it just me, or is anyone else concerned with the fact that the growth rate of new Internet users in the United States has turned into a trickle? According to data from both Nielsen//NetRatings and comScore, the growth rate for new Internet users in this country has stalled at around 5%. This doesn't look like a hiccup, either. The U.S. Internet universe has been more or less flat for more than a year