Cards that help out creature decks are always ok in my book. Wrath of God needs a weakness, and shatter needs a job.
@TheMurderousKitten
That's not exactly where I was going with that. Say you have a few creatures in play and a lightning greaves. You're pressuring your opponent, he's got a few creatures as well, and he wraths. Well, feel free to pop in a creature and swing in through his conveniently empty board.
Also, haste increases the damage output of your creatures. You want to squeeze every ounce of value out of the bastards that you can. The shroud on greaves is nice, its true, but the haste is what I like most.