I have a MacBook Pro with a 250GB hard drive and have around 50GB left. I do most of my work in the cloud though and so don’t have a fear of running out of space as I also have a 2TB eternal for backup. I think that in the future less will be done on the computer itself and more done over the web (as things go now). Th risks of this type of situation are not yet fully known though and so I think for that reason alone people will remain cautious.