LADY GAGA and ELTON JOHN
She opened the telecast with a version of ''Poker Face'' that was just slightly Gaga-by-numbers — until her musclebound dancers shoved her into the ''Fame Factory'' stage set's fiery ''rejected'' pit, and an all-time great Grammy performance began for real. When Gaga re-emerged, she was sitting at a piano across from the mighty Elton John, with matching soot smears and sequined shades. Together they nailed her power ballad ''Speechless,'' plus a brief taste of his ''Your Song.'' ''I hope you don't mind, I hope you don't mind, that I put down in words how wonderful life is with Gaga in the world,'' sang Sir Elton. Agreed! Grade: A-