There is just something about squats that nothing else can compare to. The lead up to a heavy squat session, the feeling of being under the bar during and between reps. The feeling you get after a great squat session, where your legs are still quivering hours later and you can feel your metabolism is still sky high, as your system tries to recover.
I love deadlifts too but it's almost like there is weight training and then there is squatting, all in a category of it's own.