If you believe the media, then Nebraska and Oklahoma will be the big winners in Big 12 football in 2010. According to the preseason poll, Nebraska will win the North division and Oklahoma the South division.
I'd say Missouri being picked ahead of Kansas State and Kansas is fair. Mizzou should be a tough out this year particularly with Blaine Gabbert. In fact, I'd say they have a shot to win it depending on Gabbert's progression. So much of your success in football is dependent on your quarterback.
Kansas State and Kansas will battle who should be ranked higher. Both have legitimate reasons why they should be but their votes are close enough that it shouldn't really matter.