I would not put to much focus on the concentration for O&G. The majors all recruit at top schools. I suggest looking at what schools the companies you want to work for recruit at. I can tell you that there are different pay ranges for different schools. Go to a top 5 and you will be paid significantly more than if you go to a regional program, and you will have much better career opportunities. I believe the thread on energy careers has numerous posts related to O&G, I suggest scanning that thread for details.
Kellogg Class of 2010...still active and willing to help. However, I do not do profile reviews, don't offer predictions on chances and am far to busy to review essays, so save the energy of writing me a PM seeking help for these. If I don't respond to a PM that is not one of the previously mentioned trash can destined messages, please don't take it personally I get so many messages I have a hard to responding to most. The more interesting, compelling, or humorous you message the more likely I am to respond.