With the brand new parrallel storage techniques, I say 2 years. Parallel storage drives are just hitting the market now, I beleive some Seagate SATA II drives use it. Think of it like this:
Right now we store data on drives like this: _ _ _ _ _ _
With the new Parallel technology we can store data like this: ||||||
Much more room, and much higher density of data. Cool stuff.
I remember in 2000 watching the Screen Savers on TechTV at Computex, and seeing Patrick Norton holding a hard drive in his hand say "Look at this, the first 100 Gigs". That drive came out in 2001. Look at where we are now. You can easily buy 500GB drives for under $350. That is nuts, and that is in just 5 years.