In this official Presentation for the RuPauls Drag Race brand, Lady Gaga is listed as a Guest Judge/Star.  http://www.passiondistribution.com/media/140431/drag-race_format-presentation_2016_compressed.pdf Page 15 Since she wasn't on S8 - This could lead to thinking that she will be a Judge on All Stars 2 or Season 9.  (Miley Cyrus is also mentioned even though she wasn't on S8 - So she could be there too)