Nielsen is poised to announce a breakthrough in its local TV ratings processing system that will enable it to add a fourth-stream, and that it will bring "live-only" ratings back for local advertiser,
agency and TV station clients, effective with the start of the 2010-11 TV season. Details will be unveiled later today, but it is expected retroactively to include all of the live-only ratings data
that has been omitted since Nielsen scrapped that ratings stream earlier this year.