Shadowmoor seems to overall be quite a powerful set. At least the creatures are. So many creatures are just way above the curve, with their only drawback being that they require hybrid mana, which isn't really a drawback at all. If you thought Joe's was creature heavy before...
There are a lot of cards that are interesting for more than simply being super efficient. Of these, one of my favorites is Swans of Bryn Argoll. I dream of it + pyrohemia. Unfortunately it is currently a chase rare, so that dream will be on the back burner for awhile. Another cool card is Dusk Urchins. I have been thinking of a blue/black efficient cards win deck, with the Urchins/Scarscale Ritual. The Urchins may also replace

Call of the Herd

in my G/B deck. Mirrorweave is super cool. Kitchen Finks is the new riftwatcher, Murderous Redcap may become Zach's favorite card ever, and Fulminator Mage is overrated.
All the new toys for red aggro/burn is bittersweet for me. My deck will no longer be unique, but it will rock and roll. The best thing for thrifty players everywhere is it can dominate with 0 rares.
Overall, I think it is better than Lorwyn, but still accomplishes Wizard's probable goal of it being very easy to build simple 2 color creature decks that can randomly compete with netdecks.