Interestingly I swapped my two week old HD2 for a new one today and although so far the newer one is better in terms ob battery cover and flush screen and runs smoother (though may be due to 2.02 ROM), I believe that the newer one has the same problem (or at least it will do) with the button coatings coming off. There is also a heck of a slide and play in the bar of buttons, they can really move a lot side to side if you push it around.
The older model I had had amazingingly sturdy metallic looking keys with no give whasoever. They almos seemed like real metal, whereas the ones on this newer one are very much plastic. I could swear that the buttons were segregated instead of being in one piece as well on the older one, but I think this might be my imagination running wild with me unless anyone wants to support this?