I agree with dillbob3124, DrivenByE30 & M3 Adjuster on the issue of what will the over-all size be for this car actually be. Any bigger than the E46 and it will be a definite disappointment for the enthusiast but if the looks are right then that will win the 'majority' over.
Given how car manufactures and not just BMW like to increase the size of their cars at every new change in model. It would be nice to think this new 2'er would be in between the E36 & E46.
However, as DrivenByE30 mentions it is more than likely to be at least E46 size. If this is to be the case I just hope that there is an strict condition on the designers not to let it ever go beyond an E46 size.