I realize this isn't new but I just discovered it. As if they didn't already control so many aspects of the internet, they have taken an interesting approach to music trends.
In fact, they are using the website www.google.com/trends/music to do so. Users of Google Talk have the option of connecting their iTunes, Winamp, Windows Media Player, or Yahoo Music Engine.
The way it works is that when you're using Google Talk, usually you have a status message, that shows whether you are available or busy and then also the message you have typed in. If you opt to "share your music status" instead, it will show to other users the artist and song you are listening to at the time, and when you turn your music off it will show your original status message.
When you go to Google's music trends website, you are able to view the top 20 songs for that day, for each of the genres listed in the drop down menu, for 10 different countries at that. These include punk, gospel, soundtrack, hard rock, and everything in between. The results are updated nightly to stay up to date, and you can see whether songs have gone up or down on the list in the past 24 hours. Each of the songs links to a Google search of the song or the artist, respectively.
It's kind of amazing that Google is finding success in so many aspects of the internet. What will they think of next?