Well, the full set has been spoiled. Some interesting concepts, but it looks like they were overly cautious in making things slower and more expensive. This set kind of reminds me of Invasion. The multicolored focus will help to make the set popular initially, but in the long run the low power level of the set will make the whole thing seem irrelevant. That's really too bad, as the last heavily multicolored block (Alara) tended toward a higher power level and was quite fun.
When fetchlands were officially confirmed for this set, I saw some speculation that the set was going to be weaker as a whole with fetchlands to compensate for that, because WotC wanted to use this as the low point for toning things down before having the power creep back up. I didn't think that was the case at the time, but now I'm hoping it is. Otherwise, I'm worried that they're looking to establish bland midrange as the universal deck everyone plays. Oh well, at least that would keep me from investing in Standard...