I've got a pair of XT wheels, when I hit the front brake the wheel flexes in the direction of the disc, obviously there's going to be a fair amount of torque going through the wheel but my old bontragers didn't flex like this. They've probably got around 600 miles on them. The wheel doesn't feel loose on the hub.

Is this normal for XT's?? They flex almost an inch off the center line.

low spoke tension