I would not have been the Cessna 400 size because nobody is going to build a non-pressurised turboprop for touring. Yes it would be cheaper to build but the TP engine alone will jack up the price so much that to justify the price you have to load the thing up with every goodie going. At least, that has been the conventional way of looking at it.
From the pics, it looks good. It will still be pricey - $2M to $3M - when finished.
Cessna must have noticed that Socata are still making money on the TBM so they wanted a slice of that cake... they could have made this TP at any time in the past 20 years; the only difference would have been the avionics.