It's been rumored for a while, but Seagate has now confirmed
they will be releasing a 3TB hard drive
later this year. This isn't just the usual upping of platter density to achieve a higher capacity. In this case Seagate had to overcome some fundamental problems in computing.
In modern computing systems, there is a logical block addressing (LBA) limit of 2.1TB. The LBA system can't address a capacity larger than that due to the fact that it assigns an address to each 512 byte block on the hard drive, causing it to run out of address space at 2.1TB. Seagate is using a new Long LBA format, but it requires a supporting OS.
According to Seagate, 64-bit versions of Windows Vista and 7 will work, but XP will not. In fact, XP systems may only see 990MB of the drive. Another caveat is that these drives will not work as boot drives, just as secondary drives. Current master boot record partitions are limited to 2.1TB, and the fix would be more complicated.
No one thought that LBA would be a limiting factor when it was developed in 1980, but here we are. No pricing information was available, but we imagine it will sell at a premium at first. Would you buy a 3TB drive? Or are a few smaller ones fine by you?