Pandora is forced to pay $0.10 for every song that you hear. So if you skip through three songs, you just cost them $0.30. They fought tooth and nail to get lower royalties, and their competitors with different models and millions in lobbying pay way less (Sirius XM for one). Think about it, you pay 99c and you own the song, or Pandora pays 10c and you listen to it once, if that. It's really not fair to them, they got screwed. With this cost structure in mind, it's amazing that a year's subscription ONLY costs $36.
Also, this change effects 4% of their listening public. So the author should chill when he says "limitless fountain of music would dry up to a mere trickle", because there's a good chance you're not affected.