Coincidence? / by Dan Lockton

Gmail ads related to mp3 being played?
A few minutes ago I was playing a track in Winamp, with Gmail open in an Opera window, and on refreshing Gmail, the Google 'web clip' at the top of the inbox display contained the same phrase, 'jet stream', as the track.

Is that merely a coincidence, or does Gmail monitor what music is being played by a user? I don't have Google Desktop or Toolbar or any of that installed.