If the season ended today, I think that Texas A&M would be a national seed. The Big XII Conference is one of the top three baseball conferences in the country this season. The Big XII Conference has had its conference champion not awarded a national seed only twice. And in these cases, the problem was RPI (Baylor in '00 with a 15 RPI, Nebraska in '03 with a 21 RPI). Thus far, the A&M RPI is OK (11), but could end up in the high teens if they do not win some this week.
Additionally, the big four conference champions rarely are not awarded a national seed. It has only happened once to the SEC (Arkansas in '99, 10). It has never happened in the ACC and has only happened twice in the Pac 10 (Southern Cal in '02, Oregon State in '06). Most of the time it is because the RPIs are in the high teens or twenties. Southern Cal had an RPI of 28 in 2002.
Now, if the Aggies go 0-3 in the Big XII Tournament, it gets rather dicey and I agree they probably do not get a national seed. But there are at least two games left to play for the Aggies. And right now I have little doubt they would be a national seed because I cannot see giving it to someone else. Not a fellow conference member that finished below the Aggies and not LSU (not yet). This could change as the week wraps up. If LSU wins the SEC Tournament, they will be a national seed.
Brian