Nielsen is one of the great companies that make TV profitable. They are moving into a lot of other aspects of advertising then just TV (across platforms) and are adopting to an ever changing society. Most of my blogs have been about digital analytics because that is what I am most interested in. Nielsen creates TV analytics that are necessary for understanding where a company should market. Everything from the ratings of the television show to the demographic information.
This is an awesome video of how they do their cross platform research http://www.youtube.com/watch?feature=player_embedded&v=UizO9XjaHCA
Because TV is not just watched on the television anymore it is important that advertisers understand a wholistic view of how their target market is watching TV.