Perhaps boosted by eager iPad 2 buyers, Apple’s Web site was more popular than Wikipedia in March 2011.

A new report from Nielsen, released monthly, lists the top ten web brands and online video brands in the U.S. and is a good indicator of just how Americans are spending their time online. The Apple/Wikipedia flip flop was the only major change from February’s list.

Google was the most-visited Web site in March 2011, with 152 million unique visitors. But when it comes to spending some quality time with a site, Facebook tops the list. Visitors spent an average of six and a half hours on the social network.

In online video, YouTube has also stayed at the head of the pack when it comes to unique viewers and total streams. Unsurprisingly, viewers spend the most time with Netflix — almost ten hours on average.

What are your most-used web and online video sites? What are your top recommendations?

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