Seriously guys, for any neophyte players, just remember that when the tempo gets faser, note choices become less and less important. Play chromatically if you have to, trying to hit important notes that signify important key centers when you can (like the bridge, say) while keeping the notes, whatever they are, coming. Ron Carter is one of the greatest uptempo walkers ever, and he's always preaching doing as little with your left hand as possible - trying to imply the tonalities as much as possible with the notes under your fingers without changing positions.