There is a lot of omg the sky is falling down being spread around here... Sabre was planned for awhile as was an interline agreement most likely. I could be completely wrong here but the company is doing what they are to increase profits. Implementing Sabre/UAL interline agreement makes total sense and will increase revenue. Passengers will go nowhere since they will still be buying a ticket under the UAL or Silver reservation system. Maybe they will want to go it alone one day, but that is not the goal right now.