Media Buyer Planner writes:
"XM Satellite Radio will ship to retailers in two week the two XM-enabled portable MP3 players that will make push-and-purchase transactions possible through radio. The logical next step, allowing advertisers to use the push-and-purchase technology, may not be far behind.
With the new XM MP3 players, users can press a special button on the device to bookmark the songs they like.
-- via Hill Holiday, more at Ad Age