Online video measurement took a big step closer to television today with the news that Nielsen has struck an alliance with video ad network Tremor Video to include gross ratings points data in online video buys.

GRP's are the currency of the TV business and media buyers have contended that for online video ad dollars to grow big and to snag share from TV, the measurement will need to be consistent.

Under the deal, Tremor will incorporate Nielsen's Online Campaign Ratings gross ratings points in its VideoHub, a reporting and analytics tool that Tremor launched in the spring.

Tremor said the new partnership marks the first time Nielsen's GRPs will be woven into a video ad platform. The partnership will allow the two companies to tie the familiar GRP metrics to online video performance to give marketers a measurement of reach and frequency across the mediums.

Marketers can also tap into demographic information on their online video audiences and how online viewers are responding to their messaging.

We interviewed Tremor's Anthony Risicato about the VideoHub earlier this year.

Daisy Whitney