Interviewer mentions will.i.am because both girls are working with him at the same time
Britney confirmed ALIEN in another interview, produced by William Orbit [Ray of Light producer] is a song on her 8th studio album "Britney Jean" which is executive produced by Will.I.Am
Britney also confirmed there's some anticipated collabs on Britney Jean
Will.I.Am is also a confirmed producer on ARTPOP
Will.I.Am recently tweeted this to Lady Gaga
Not to mention that both were spotted multiple times at the exact same LA Studio earlier this Summer.