Both.
Or, I could go with the National Championship because it probably means we took the Big 12 Championship along the way.
If I'm truly honest though, I'm pretty fixated on a Big 12 Championship. With the media and blog world giving us less of a chance of winning the north this year than last,* I'd really love to take the division and win that title game in Kansas City.** Plus, thinking about the MNC popularity contest, it's really so out a team's control, you obviously think about that national picture more in November (or maybe after Sept. 12 in our case). The conference title makes a lot more sense. You play some exhibition games, then you head into your conference and battle it out. A poor game here or there shouldn't knock you out of the title game.*** Anyway, I like the simplicity of the Big 12 race -- it's all decided on the field. Plus, 1968 was too long ago.
*Seriously, a 6-6 team that lost Jon Cornish, the interior of the offensive and would be guided by a new sophomore starting QB got more talk about winning the north than this 12-1 squad with 9 starters back on "D" and a proven "big-time" QB. I long for the optimism of August 2007.
**Reminds me -- I need to get my tickets.
***Actually, I think it did last year. Although, I guess I have to give Missouri some of the credit.