The foot soldiers of Arbitron might be wondering why they had to sacrifice years of their life for this outcome. I'm sure no one who suffered from the competition between the two will get any part of the 1.26 billion. (Full disclosure: I was part of Arbitron's TV & Cable business from 87 through its death in 1994, so I have been in their shoes.)
On the other hand, Nielsen does get working audio-driven, passive personal people-meters out of the deal.. Arbitron was working on them as a replacement for ScanAmerica's STB back in 91, so they've had some time to get it right.
Nielsen's not been the best at following through on announced technology roll-outs. (Remember mailable meters?) What they are good at, it seems, is spending money to buy out competition.