The more I think about it, and the more I think about past history at both BGT and SWO, my gut is telling me that we'll see a new coaster at BGT in 2016 and a new coaster at SWO in 2017 or '18. Look at the span of time between Kraken and Manta: 9 years. We also don't see a lot of obvious activity going on at SWO right now...if they're going to open a new major coaster for next year, we're going to have to see major construction starting in the next few months. And seeing as how coasters are NOT the major focus of SWO, 2015 seems a tad early for a new mega coaster. Now BGT on the other hand is ripe and ready for a new coaster in 2016. Cheetah Hunt will be 5 years old and paid for (not to mention likely fully depreciated for tax purposes), Falcon's Fury will be 2, and the timing will be right to see a new mega thrill coaster drop. I wouldn't be surprised to see Gwazi stick around for the rest of the year, only to be demolished early next year for a new coaster opening in its spot for May 2016.
I'm no insider/expert...I'm simply speculating.