Pandora Radio: Safe or Unsafe?

Pandora Radio is a popular and widely used application used on smartphones and internet browsers across America. This radio services allows users to search by artist, song or genre and it will coordinate a set of tracks similar to your search. How safe is Pandora radio, however, with our information? A recent article from the NY Times states (view article):

"The online radio service Pandora has received a subpoena from a federal grand jury investigating whether popular smartphone applications share information about their users with advertisers and other third parties."

What exactly does this mean, you ask? Pandora uses our information and delivers it to other companies to track how we interact with the service for advertising purposes. This type of issue seems to be coming up in other sites that we use frequently. The FTC is proposing a "DO NOT TRACK" tool so users will not have their information shared. I think this goes to show how unsafe the internet really is. One minute, a new innovative product or service is being discovered and the next, information is being passed back and forth that hasn't been agreed upon.

What is your opinion? Is this sharing of personal information going too far? Or, is it okay for companies to do without our consent?