Then True Temper OX Platinum, then Dedacciai COM12.5. But actually the 'True Temper OX Platinum frame' only had two True Temper tubes in it. And Dedacciai COM12.5 is a lower level tube than Dedacciai COM14.5. So the down-grading has been going on for quite a while.
I guess people have become less interested in what tubes are used, as forks, brakes, geometry, wheels, drivetrain have predominated in buy decisions. The current Explosif appears to be a Lava Dome with Explosif stickers at an Explosif price. If that's what people want, then you can't blame Kona for selling it.
I would far prefer a 2010 Blizzard to a 2010 Explosif, but then a 2010 Blizzard is £900 for the frame alone!