Brooks made the Hyperion Elite info public now.
Feb 27th. $250. It is designed more for stability than energy return. The DNA Zero midsole is a light EVA. Much firmer than the Vaporfly. The DNA Flash in the Hyperion Tempo is actually more responsive and is a nitrogen infused EVA with small and uniform air bubbles to increase responsiveness, which sounds like their version of Hyperburst.
This sounds like a dud. The Hyperion Tempo sounds nice as a 8mm Hyperburst-like speed trainer. But they have already admitted their $250 elite racer has less energy return and is just a light EVA. If they were selling it for like $180 like Hoka's EVA carbon plate shoes MAYBE, but Skechers and Saucony will drop their racers with better midsole for less money.
It seems that NB, Saucony, and Skechers will be the real competitors here.