No its not, I used it for a few months and the novelty was awesome, seemed to have everything. Was able to play the Indiana Jones and the Temple of Doom child slave music while my sisters kids were working in the yard, was hilarious.
Then I was told about www.grooveshark.com which is a music streaming service where users upload the music so you get various different qualities to choose from, and it has everything a user could upload and the nice thing is its FREE and it works on the PS3 browser, flaky at best but it still works if you have all your songs lined up and ready to go.
EDIT: You can only use it on one device at a time, and IIRC it only works on the PS3 and PC/Mac, and as far as I know there is no support for any mobile device other than PSP. --- http://www.terra-comic.com --> Terra: a Science Fiction Webcomic / Updates every 15th of the month.