lenses are loose when mounted.

I've noticed this with more than 1 body. When I mount a lens (any of them), the lens has a bit of rotational free play. When I mount the lens to a tripod or monopod, I'll hear little "klunk" sounds as I touch the camera and it rotates ever so slightly and bumps up against the lens locking pin.

Is this normal? Neither the lens (new) nor the camera show any significant wear on the locking parts so I'm concluding that it is just normal slop.

how much? there should be about 1mm worth of play

if there is much more than that you will have to probalby replace the mounts.. I have to do that this summer with a 300 2.8

The only thing lose on any of the bodies or lenses I've had is when using a Kenko tube. They are sloppy. None of my lenes on any of the bodies were lose at all though.

There is a tiny bit of play in the mount. Some lenses are tighter than others as well.