Actualy, the 50 mp high ISO images decompress to about 150-200mb, and they are a pain to post process, particularly with brush adjustments in LR and adding NR. I've processed 700 images from a nights shooting with my D800 and with a reasonably fast computer, and it takes much longer to post process than a 22mb 5D MK III. Storage is not the issue, its cheap, but having to change CF cards twice as often is a pain. I finally bought 64mb cards to help with that.
I'd have no problem with storing 36MP files, or even 60MP files for that matter. No problem with processing them either.
Storage is definitely getting cheaper.... I remember when hard drives dropped below the $1.00 per
level. Now it's around $1.00 per 20 gigabytes... And I have a drawer full of 32Mb compact flash cards at work.....
As to processing speed, GPU assisted programs are slowly finding there way into use. By using the graphic processor you can execute parallel tasks off of the main CPU, and depending on the nature of the program and data, can speed things up by a factor of ten or more. A good example of this is Autopano Giga, which can use the CUDA cores on an Nvidea graphics card to speed up rendering of panoramas. A high end card has 1000 1Ghz CUDA cores... Lots of computing power. There have been supercomputers built using graphics processors.
I would expect to see GPU processing getting more common in software as time goes on.