Pop star takes on her critics prior to release of new song 'Do What U Want'
'Do What U Want' is available to download now
New 'ARTPOP' track featuring R Kelly will be available from Monday (October 21)
'Lady Gaga & the Muppets' Holiday Spectacular' will also feature Elton John
Song will feature on new album 'ARTPOP', due for release on November 11
'ARTPOP' star reportedly shot the holiday special in Los Angeles
US popstar posts 12 seconds of the song on her YouTube channel
Singer announces her next 'ARTPOP' single on Twitter
R Kelly, T.I. and Twista will appear on pop star's third album, due out in November
Artwork appeared on Clear Channel billboards worldwide at 6pm GMT today (October 7)