Actually there is a very good reason to lower the price. With the new one out nobody will buy the old version at an equal price. Everybody who wanted #10 probably got it during the pre-order period. Why not slash the price of #9, and maybe bring in a few "on the fence" types? Get them interested, and perhaps they will upgrade to #10 after "putting their toe in the water".
Seems a sensible course of action to me.