ComScore is the leader in estimating World Wide Web traffic to top websites and releases monthly reports on the most visited websites across the world. ComScore released the list of the 50 most visited sites in the US as part of its report on monthly analysis of U.S. web properties activity.

The 50 most visited US sites list (PDF download) is available from their website and it shows the following top websites.

It comes as no surprise that Google and it’s related web properties are the most visited websites in the US. Facebook holds an enviable fourth most visited position, even more than sites like Amazon, Apple and eBay, and far far above Twitter and LinkedIn.

MySpace still seems to be holding in the top 50 list, while the surprise new entry is Pinterest, which shows the growing popularity and traffic of this new social media service.

If you want to see the official announcement from comScore here it is. Which website you expected to feature on this list and it’s not there?