Is power over the Web concentrating in a few corporate hands . . .

. . . as happened years earlier to the TV and newspaper and book publishing industries?  According to Michael Wolff in the Sept. 2010 issue of Wired: "the top 10 Web sites accounted for 31 percent of US pageviews in 2001, 40 percent in 2006, and about 75 percent in 2010."