Amazon has announced that it will launch a digital music store later this year. The store will offer “millions of songs,” from more than 12,000 record labels, all in DRM-free MP3 format. The store will include EMI Music’s catalog. “Our MP3-only strategy means all the music that customers buy on Amazon is always DRM-free and plays on any device,” Jeff Bezos, Amazon.com founder and CEO, said. “We’re excited…