Vastly superior to Falling Skies, Terra Nova and Revolution combined.
This is true, but it's really not saying a lot.
Like Babylon 5's pilot, Defiance throws an expansive world at us with a half-dozen clearly important alien races and around a dozen Important characters.
Unlike Babylon 5's pilot, though, which appended this heavy duty exposition to a relatively low key murder mystery, the pilot's already moving the plot - killing off characters and setting armies on our heroes before we're more than vaguely clear of the importance of either.
It's promising, this said, the most promising Syfy pilot - hell, science fiction pilot - I've seen since Caprica. I'm hoping Kevin Murphy does a better job showrunning this than he did that, but who knows?