I reckon Radiohead have been innovative, and I blame Radiohead for the unprecedented amount of shite that is out there at the moment.
Vocalists who try and imitate Yorke's voice (which only ever sounds good (most of the time) when it is Yorke himself singing a Radiohead song). Yorke-wannabes come off sounding more whiny than in genuine despair, and their lyrical themes are nowhere near as genuine and as honest as Yorke's.
There are some Radiohead songs out there that I can't help but think of as producing an unprecedented sound in music history - namely Pulk/Pull Revolving Doors, Worrywort, Airbag, Kinetic, The Gloaming, Myxamatosis