The NCAA released its first softball RPI of the season, so it's time for the inaugural Stats and Information Softball Conference Power Rankings for Week 1.

The most notable thing to come out of this week's rankings is that the top conference is not the Pac-10, whose teams have won 23 of the sport's 29 national championships, or the SEC, which features three of the top four teams in the RPI. Instead, the Big 12 earned the top spot by placing Texas, Missouri and Oklahoma in the RPI's top 10, and having only one team, No. 76 Iowa State, fall outside of the top 40.

Why is the SEC a distant third? The simple answer is that three of its schools -- Mississippi State (79), Arkansas (124) and Mississippi (168) -- rank outside of the top 75.

Like the Big 12, the Pac-10 possesses great balance: Only No. 99 Oregon State falls outside of the top 25. Further indication of the conference's top-to-bottom strength is that its second-worst team from an RPI standpoint is No. 25 UCLA, the defending national champion. The Pac-10 trails the Big 12 by less than a point, so check back next week to see what, if any, movement there is in our rankings.