It is a "juggernaught" still... Where Turbo Tank came from I'm not sure, probably just LFL speak for it during ROTS production, but it's originally concept art fot the Imp. AT-AT way back when, that got axed and like a lot of other conceptual designs it got picked up by the initial EU gurus at West End Games who said it was a Republic Era armor design that was used into the Imperial era known as the Juggernaught...
For my tastes as a military fan, I will forever call it the Juggernaught... Turbo Tank sounds like something you revved up along your tile floor as a child and let it roll. Very dumb.

That was a nice answer overall though in general... I'm not a fan of Hasbro's efforts with larger vehicles myself, but I'm sure that makes people happy. The answer fleshed out a vehicle people have wanted since ROTS. I personally don't think I'll be wanting one as I'm sure it'll be too small for my tastes, but kudos for the thought put into it and whoever it makes happy.