So far Lionel Richie and Foo Fighters have been confirmed.

I also think we will see:
Florence and the Machine
Royal Blood
Vaccines
Ellie Goulding
Clean Bandit
Noel Gallagher

Well we got a headline act (first?) confirmed

and it's the mighty Foos

http://www.nme.com/news/foo-fighters/82926

edit: now I see

First rumours about Adele

Heard the Adele rumours! As much as I live Adele, I don't think her set is suited for Glastonbury.

Unless she throws out a few pop stompers on her new album

Apparently the Foo Fighters have been announced as Friday's headliners.

Royal Blood have been announced as a 'festival exclusive' for Reading & Leeds, but some or most of the others seem like decent shouts.

Lulu.

Kanye West

Told ya.

Pleased with Kanye, should be a great show.

Good on you girl.

Thank you, sweetheart!