sucker punch doesn't tend to overpromise, though. the devs for heavenly sword, uncharted, lair, and killzone 2 all talk(ed) a lot of shit about their engine and their physics and their facial animation routines and their ai and talk(ed) very little about gameplay mechanics, game design, or reasonable hardware expectations. infamous isn't an ambitious game -- it's just one with a cool design sufficient for a superhero-based nerdgasm. there's nothing in that preview beyond some gi-spawned hyperbole that isn't capable of being effectively realized on a next-gen platform, and given sucker punch's track record, i'm safely optimistic. there's very little pseudo-technical in that preview for the sony set to latch onto, and thus feed the hype machine that catapulted the titles you mentioned into undue prominence.
well, i think. i do occasionally underestimate the fervor of this generation's gamecube's fans. still, i think infamous is more re4 and less rogue leader, as it were.