Executive chairman Itzhak Fisher (formerly holding the same title with BuzzMetrics) will head up Nielsen Online--and the service will bundle the company's Nielsen//NetRatings and BuzzMetrics services.

Advertisers, publishers and agencies seeking measurement of blog and social networking traffic, e-commerce and online shopping behaviors, as well as insight and analysis of Internet video and advertising metrics, will find that the service has Web 2.0 covered.

Sid Gorham, former president of Telephia, will head up Nielsen Mobile--an amalgam of Telephia (which Nielsen acquired in June), the company's recently launched Nielsen Wireless measurement service, as well as other unnamed, but ongoing mobile initiatives.

Nielsen Mobile also combines bill-scraping data with insights from a panel of more than 40,000 mobile users to give advertisers, mobile service carriers and content providers a read on what mobile users are actually doing with their phones and their attitudes toward the media content on them.

Both divisions will continue to offer panel-based and tech-based direct measurement (like the Nielsen People Meter) to provide the most comprehensive view of audience behaviors. According to Kanishka Agarwal, vice president of Mobile Media, Nielsen Mobile, the two departments will collaborate to better answer questions like 'How many males ages 25-34 visited my Web site via their desktop and mobile phone?' and 'Which medium is best for reaching Hispanic sports fans on Thursday evenings?'

In the coming months, Nielsen will develop products that combine data and insights from Nielsen Mobile, Nielsen Online and Nielsen Media Research (for TV) to give advertisers a holistic view of their target's behaviors and demographics on all three screens. While info for mobile game downloads will be tracked by Nielsen Mobile, insights for PC and console games and downloaded mobile ringtones will continue to come from Nielsen Entertainment.

"When you think about advertisers--they want to buy audiences, not time in a TV show or space on a Web site. They say to their agencies--I have 'x' dollars to spend to market this product to the right audience, so help me make the right media buy," said Agarwal. "And with Nielsen's services now both of them can figure out how to better allocate dollars across those three screens."

Agarwal added that the products, research and analysis coming out of Nielsen Mobile and Nielsen Wireless would continue to evolve and be released to help media providers, advertisers and press alike understand how consumers are using the Web and their mobile phones.

For example, Nielsen is investing in an on-device mobile metering service, similar to the People Meter, that will cull data from consumers who opt-in to have their mobile media consumption monitored.

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