I've not pushed the new or old versions of 400, but in terms of underexposure latitude, (which I would think is related to pushability), in my experience, the new Portra 400 isn't *that* different than the old 400NC/400NC.
I am happy, because I could never really choose between the VC and NC and found myself thinking about film choice too much. I prefer thinking about the pictures...
Peter from Kodak just replied to my email about Portra 800.
I see that the technical datasheet E-4040 for the Kodak Professional Portra
Films, (160NC/160VC/400NC/400VC/800) is now listed under the discontinued
publications list, but the Kodak Professional Portra 800 Film continues to be
available in 120 and 135.