How are the measurements used by Nielsen evolving to meet new methods of content delivery and viewing?

Question

I was interested to find out that in the 1950s, Nielsen used devices in the homes of the families that were surveyed to record their viewing preferences, and only later introduced their system of using a diary to record habits:

...in 1950...This information was collected on a device that was attached to a television that recorded what was being watched. In 1953, the company began sending out diaries to a smaller sample of homes (“Nielsen families”) within the survey to have them record what they had watched

from Wikipedia

So, presumably as multiple different viewers in the home were considered in the sample, the means through which the ratings were recorded changed.

Given that so many people are able to record shows digitally and watch when convenient and that so many view their favorites on outlets such as iTunes, how have the Nielsen ratings systems adapted (or how does the company plan to adapt them) to capture our modern viewing preferences?

While a DVR-recorded show still technically makes its original "timeslot" relevant to the equation, will Nielsen consider timeslot-specific data a hindrance to comparisons between those shows viewed on cable and the same show viewed on iTunes?

Answer 1

From Nielson.com (retrieved Dec 2012):

How We Do It

Panels

Electronic metering technology is at the heart of the Nielsen ratings process. Our tools capture not only what channel is being watched, but also who is watching and when, including “time-shifted” viewing.

Nielsen’s TV families represent a cross-section of representative homes throughout the U.S. Their viewing is measured by our TV meters and Local People Meters which capture information on what’s being viewed and when and, in the major U.S. markets, specifically who and how many are watching. Additionally, we collect more than two million paper diaries from across the country each year during “sweeps.”

Census

Using data from set top boxes, Nielsen delivers a constant, real-time stream of information, revealing tuning behavior during programs and commercials. We can tell clients which commercials are being watched and which have the strongest engagement and impact. We even analyze which position in the program or commercial block is most effective for a specific brand.

Cross Platform Measurement

We measure national TV viewing using Nielsen's People meter technology to electronically capture all viewing from our nationally projectable sample of panelists.

Nielsen representative panels of Internet users provide browsing and streaming metrics for online users. Using census-based measurement, we provide in-depth tracking and analysis of site performance as well as information about audience consumption of, and engagement with, streaming media.

And for mobile media, we are pursuing on-device meter panels to record every interaction users have with measurable mobile devices, which complement our robust survey data.

Finally, through single-source panels along with modeled databases, we measure how consumers engage with multiple media platforms.

There is a short video at the link above.