I doubt very much it's ending in 2015. They make too much money in this business and have for decades. I also think there will still be some market for 50-seaters, especially since by that time many will be paid for outright or on very favorable lease terms. NWA made money like crazy flying 'out of date' DC-9s.
Everyone knows that things need to change here eventually. That's not a secret but you can't just go out and order airplanes without a contract in place to fly them.
As to the CRJ-900 rumors? Well, they've been talked about for years. I know for a fact that years ago they began to put together a syllabus for the training department for the CR9 but nothing ever came of it. I will believe it when I see it on the ramp or hear the announcement from the company. There is no payscale for the CRJ-900 at the moment anyway or even for a 76-seat airplane.