ComScore Tweaks Ranking Methods, But Top US Web Properties Mostly Unchanged

Google, Microsoft and Yahoo were the top three most-visited web properties in the US in August — just as they’ve been for many months, and despite comScore introducing a few changes in how it estimates website traffic.

In sharing the August 2012 numbers from its Media Metrix service, comScore says it’s introduced three changes to how it ranks websites:

The first enhancement is the incorporation of updated demographic universe estimates based on data from the 2010 U.S. census, which provides an improved accounting of the percentage of the population falling into each demographic segment. The second enhancement was an improvement in comScore’s enumeration survey methodology to better represent persons in cell-phone only households. The third and final enhancement is a new technique to account for cookie rejection in Safari browsers, for sites measured via comScore’s Unified Digital Measurement (UDM) methodology.

Despite that, there’s not much change in the August rankings. The top seven most-visited properties are the same as they were a month ago. Apple dropped out of the top 10 and ranks number 11 for August. ESPN saw a significant traffic gain in August (perhaps Olympic-related and/or NFL-related). Here’s the full top 50.

Due to the changes in how it estimates traffic, comScore has cautioned against making any month-to-month or year-to-year comparisons in its data.