In addition to contracting engineers to make sure that the wind and rain would disproportionately hit the visitors' sideline, [the stadium's architect] placed the cheapest endzone seats (where, he says, the "crazies" sit) atop steel risers that send thundering noise to the hard surfaces on the overhangs and roof, redirecting it back to the field.
I remember a few years back when an employee of the Metrodome turned on vents to help Twins' fly balls become home runs. And in recent years college football's SEC conference and the NFL have both legislated against artificial noisemakers. The NFL's rulebook even has a section devoted to phrases that may not appear on jumbotrons: "Pump it up" and Let's go crazy" are both prohibited.
We've witnessed an arms race with respect to new football stadium construction. The pink taco has a roll-out natural grass field. The Cowboys' new venue will have a 60-yard-long HD scoreboard. But after the Seahawks' success in their new super-loud digs (29-11 since moving to Qwest Field!), you can expect other teams building new homes to ratchet up the acoustics - and especially the weather - to extend their own home-field advantage to Seattle-like levels.
What can the NFL do about this? Seems like the seahawk has flown the coop.