With the introduction of the Toyota Supra, rumors have been swirling that the 86/BRZ twins might not be replaced when their production lives were up. Autocar UK has a quote from Toyota's European Marketing Chief saying "[the GT86] has been a successful halo product for us" and added that "...the Supra is not to replace that car."
The 86/FR-S/BRZ was released in 2011 as a co-development between Toyota and Subaru. It uses Subaru's boxer engine and transmission. It is highly likely that the next generation model would continue to use the signature engine. The new car would continue sit below the Supra in the Toyota lineup. Akio Toyoda has stated interest in building a full lineup of sports cars.
Whatever comes from the next generation 86, we're just glad that SUVs haven't killed yet another sports car.