I like the teleporting/moving capability of PCs. It lets them move into advantageous striking positions, or it lets them move monsters into disadvantageous positions, perhaps in the range of a defender.
I absolutely *love* the Tide of Iron power. I want to play a tough dwarf fighter who shoves bad guys around, and this power lets me do it. It also lets me shove a guy off a cliff, into a trap, into a group of bad guys so my wizard buddy can fireball their asses, and so on. That's really cool enchanting.
And the bad guys will likely do it all too, so it's not unbalanced. The 4e battlefield appears like it will be much more dynamic and fluid than the 3e one.