Firmware 2.70 that went unmentioned by Sony regarding the MP3 player. Before, in order to assign album art, you had to use a program like Sonic Stage to embed it within the MP3 file. Now, with the new version out (2.70), you can simply put the JPEG file in the same folder as the music, creating the art for the playlist. Very useful when trying to organize your music.
Source: pspupdates.com