We hear about holographic storage time and again, but look around — do you see any holographic drive arrays around you? Didn't think so. At the moment it's just not cost-effective (compared with plain ol' HDDs) and not fast enough (compared with SSDs and other flash arrays). That doesn't mean it'll be an exotic technology forever, though: GE is hard at work making it more compatible with existing technology, and thinks they've come up with something good. Their optics labs have increased reflectivity in their media to the point where a standard Blu-ray laser can be used to read them, though nothing is said about writing.
The resultant discs, the same size as CDs and DVDs, would be able to hold 500GB at current densities, going up to 1.6
GBTB in densities achievable in a year or two. What does this mean for you? Probably nothing, but it's good to know they're all hard at work, right?
Maybe in 2011 you'll be able to buy a modified Blu-ray drive (assuming the format is still around) that will have a mode for reading these holographic discs. You might even be able to get a special drive to write on ‘em. Seems a bit weird talking about “next-generation” optical technologies when almost all media is going online, but there's always a use for discs like these. Assuming the discs aren't too volatile, this kind of storage capacity would be great for backups.
Aaanyway, don't worry your little head about it. When something happens, you'll know (because we'll tell you). In the meantime, get your holographic storage shirt here.