Why would someone use resurrection? You have to pay target spell's mana cost and the spell level. I don't really understand why you would not just summon a creature. I guess I can see the value if you had a epic card which you are only allowed to have 1 in your deck. If you were using it on a non epic card, you might as well just have a second card in you spell book. Resurrection is a level 4 spell (and often is an off spell school).
I assume when you summon via resurrection, the creature still can't act this turn.
Any ideas?