Yep, you need 14 chops with Steel pickaxe to harvest Iron ore and only 10 chops with Iron pickaxe.
There is no such problem with Axes (7 chops for Iron and 5 for Steel), but I can't say that there is any difference between hammers =(
p.s.
Also there is some problem with handgun animation:
(http://i.imgur.com/nn68Rsx.png)
I can confirm this.
I always run around with a steel axe and copper pickaxe, since copper is better than steel :P
Yup, that was a mistake in the specified values for these pickaxes.
It's fixed now and everything was also rebalanced slightly.