To each his own I suppose.
This is my opinion: Neat and all, but I prefer WWII area. I'm sure some are overly excited for a WWI arena, and thats fine. I still prefer WWII area and the leaps and bounds in technology that came from that area. I may try it couple times, but WWII era is why I'm here. 
Very cool, really... but ditto what 5PointOh said. I'm here for WWII, even though the WWI stuff is really very cool. I hope it all works, and gets support from the community because variety is good. I'll play it and maybe learn to love it. We'll see. I guess I'm warming up to it.
I'll prolly be more excited about building missions with the new planes. Pea-shooter missions.