During the holiday season, both sites offer free Christmas music. iTunes usually offers two songs each week, with the new songs being offered each Tuesday. This week's offerings are from Faith Hill and Brian McKnight.
Amazon has a much bigger selection of free Christmas music than iTunes. They are doing a 25 days of Free music. Today's free selection - Greensleeves done by Vince Guaraldi. Much cooler than Faith Hill or Brian McKnight. The selections are free all month so if you've missed days 1-10 so far, it's not too late. A new selection is introduced each day. They also have a free holiday music sampler with artists like Bing Crosby and The Beach Boys. If you poke around a bit, you can find other free music, too.
So there is my early Christmas present to all of you - free music. Get downloading.
Last minute addition: I'm adding this to the list because I just found out about it. My favorite radio station in Philly, WXPN, is doing a 12 Days of Local Christmas Music. All the downloads are from Philly Local bands. Today is day 3, but you can download past days' songs, too. And, of course, it's FREE!