What I like in the article are the quotes from the tracker and advertiser also ran. Basically, how can you trust anyone who uses Twitter to talk about privacy?
As for the discussion about user profiles and ads, I'd like to see more research into the whole idea of whether knowing so much about someone really makes that much of a difference when it comes to product advertising. The general assumption is that it does and this is why advertisers are prepared to pay more for it, but I'm personally not that convinced. Contextual adverts are certainly the ones I respond best to. Of course, the two approaches meet in services like Spotify and Netflix (and boy do they both love our data).
I've thought for a while that Google has a greater understanding of personal versus aggregate data. For example, in most cities it probably has sufficient aggregate data to suggest where would be a good spot to put a hotel or a chinese restaurant, or cycle lane. I'm sure there's a great deal of trade in such data and find it strange we don't hear much about it.