Grounded for me. I've tried hovering but feel totally uncomfy with it and then start worrying "am I hovering this too high". There again it stops one of the 3474 swing thoughts entering my head
I ground it while I place my feet, then lift it and let it hover for a moment before I begin the takeaway. I want to feel the clubhead in the same position behind the ball that I want to have at impact. Always feel that when I leave it on the ground and start my backswing from there, that I will return to that and hit it fat. (Only for the driver, though, all other clubs I leave on the ground until I begin my backswing, unless there is an especially nasty bushel of grass behind it or something)