TV ratings company Nielsen is to change its definition of what constitutes television viewing, according to the Hollywood Reporter. This would mean that data from streaming services such as Netflix and Amazon Instant Video, viewed on devices from set-top boxes to the PlayStation 3, would be included in Nielsen's ratings. A committee made up of representatives from TV networks and advertisers reportedly agreed to the changes at a meeting in New York on Tuesday.

Nielsen has been working on the necessary analytics technology for a while, with pilot programs studying Hulu, Netflix, and YouTube streaming, as well as with cable companies' tablet applications. The Hollywood Reporter's sources say that Nielsen plans to roll out new hardware and software in the 23,000 American homes it draws its data from this September.

Initially, only a limited amount of data will be taken from tablets, such as the iPad — the primary focus is said to be on set-top boxes and game consoles. Nielsen has reportedly targeted the end of this year as a goal for measuring iPad figures. The ultimate goal is "to capture video viewing of any kind from any source."

Update: The Los Angeles Times has now confirmed both the new additions and the fall rollout, with CBS chief research officer David Poltrack saying "It is imperative for us that Nielsen as soon as possible incorporate these new forms of distribution into the overall measurement system."