I know Google Music Trends (http://www.google.com/trends/music) has been discontinued, but the "Show current music track" option is still available in Google Talk. I guess that function is still there for your friends to see?

More info:

http://blogoscoped.com/forum/128222.html
http://blogoscoped.com/archive/2006-08-17-n27.html
http://googlesystem.blogspot.com/2006/08/google-music-trends.html
http://groups.google.com/group/google.public.support.general/browse_frm/thread/dc0a2b4a93aec569/9c1ddcb8ee37e3df?#9c1ddcb8ee37e3df

The latest version of Google Talk is from early January 2007