Well it did change a lot from 8 to 9 according to mike, he says the 09 dm is a huge improvement over the 08.
But, I agree just look at the gun values! I have seen used clones go for 1200 while I just saw a brand new in shrink wrap dm12 go for just under 900 on eBay.
Gt is just plain newer tech... I kinda think dye has pulled the nt off the market for a while so that they can do something really special with it, really put a solid gun with new tech on the market. Then maybe phase out the dm, idk but that just makes sense to me.