Newly released data from comScore puts Internet radio rep Targetspot’s network at the top of the “Entertainment-Radio” category for the month of February. Targetspot reps all of CBSRadio’s Internet radio sites which include AOL Radio and Launchcast as well as CBSRadio’s broadcast stations’ streams. In addition, Targetspot sells streaming audio ads on Slacker, MySpace Music and GOOM Radio.

It’s no surprise that their reach is large and their rank in comScore shows that is indeed the case. A Targetspot press release touts the info, saying “the company reaches more than 64% of the Entertainment-Radio category and 14% of the total Internet audience.”

It’s good to finally have some data to quantify the extent of Targetspot’s network reach. It’s important however, to understand what this comScore data is telling us, and what it is not. This ranker measures the number of persons that visit a website, not the number of listeners to a stream. The “Entertainment-Radio” category compares networks with websites in that category, and tracks traffic to those websites. comScore’s data is a useful tool for selling website impressions such as display banners.

So while it is good information, it’s data that is not about the number of listeners that a station has, and it’s information that is difficult to use to sell or purchase audio ads. It’s not as good as it would be if we could finally see the Targetspot network measured in AndoMedia’s Webcast Metrics report – which is a report that contains data about listeners to streams rather than visitors to websites.

This is Targetspot’s first inclusion in the report, which also measures Clear Channel Online, Pandora, Westwood One, and ReplaceAds’ network. Targetspot aggregates more than 29 million unique site visitors within its network.

The following chart shows the adjusted comScore data from the top five companies in the Entertainment-Radio expanded category report ranked by largest audience:

                                                       Total Unique     %
Rank                        Name                       Visitors (000)  Reach
-----  ----------------------------------------------  --------------  -----
1      TargetSpot - Adjusted Reach*                    29,452          64%
2      WestWood One Partner Sites -potential reach     27,430          59%
3      ReplaceAds - potential reach                    18,638          40%
4      PANDORA.com                                     12,556          27%
5      Clear Channel Online                            9,164           20%
       * Based on adjusted numbers released by
       comScore on 3/10/10