Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of Rentrak (UNKNOWN:RENT.DL) were flying through the roof today, gaining 27% after it reeled in CBS (NYSE:CBS) as a subscriber.

So what: The provider of media measurement tools said CBS had become the first major subscriber to its TV Essentials package, which will give the broadcaster hourly ratings from more than 230 networks and vehicle models. CBS' Chief Research Officer, David Poltrack, explained, "As more advertisers move beyond age/sex demographics for their media buying, there's been a shift to combined data with product-purchase data to create comprehensive tools," which he said Rentrak exemplified.

Now what: Poltrack's vote of confidence is perhaps the best argument around for an investment in Rentrak, which calls itself the leader in multi-screen measurement, as the company appears to be gaining a competitive advantage in this niche industry. Shares of TV broadcasters have soared in the past year as companies fight over limited spectrum, so it only makes sense that the advertising data that fuels the industry would become more valuable along with it. I'd expect Rentrak shares to continue to move higher.