This can be a really great finisher if you're losing. I know that sounds like an oxymoron, but it only really works if you have more than a couple big threats in your graveyard, which probably means you're losing. If you have only an Angel of Serenity and a Reya Dawnbringer in your yard, you'd be better off casting Resurrection since you're only getting one back anyway. Increase the number of threats from 2 to say, 8 and suddenly this card gets some added value. You'll be getting multiple creatures back to the field even though you have to exile the others. The exile is kind of mitigated if you have no way to get the cards back anyway though and if you're losing, the exile zone is pretty much the same as the graveyard, right? This card does take some talent and timing to use properly, but if you can pull it off, it's can be a reversal-in-a-can.
Pros: Mass resurrection
Cons: Only brings back some of your creatures, exiles your creatures, requires fairly large yard for maximum value