Wow, yeah, good point on the NFC rotation.
Conflicting info out there (looking at you,
JohnnyRoadTrip.com), but yeah, Seattle was here and Arizona was there in 2009, so it would make sense for to be flipped in 2013. But even wikipedia has the Texans headed back to Arizona while the Seahawks play in Houston.
http://en.wikipedia.org/wiki/2013_Houston_Texans_season
Also, based on the rotation theory, KC is an away game and Oakland is a home game for the Texans. The reverse was the case in 2010 when the AFC South last played the AFC West.