I like the folks at Rentrak and I'm not snarking on their data. I don't blame Rentrak at all for riding any and every anti-Nielsen wave generated by the media. Besides, data-based businesses can be extremely lucrative, even if you are the redheaded stepchild.
Instead, I'm snarking on a MediaWeek headline of "Rentrak Moves in on Nielsen." I won't blame the author, because that headline could've come from an editor.
Having read the article my headline is more accurate. Nobody is using Rentrak data instead of Nielsen data. As ever, it's a secondary data source. Despite the the bogus headline, the story itself is quite good and notes some of the uses and limitations with the STB data.