Capacity and price seem to have peaked. I have watched both carefully for over a year and there has been no price movement down for 3 & 4 TB drives and no sign of bigger ones.
This has been very frustrating to me. After the 2011 Thailand floods that caused shortages and prices to jump up - which have only just recovered - there doesn't
appear to have been much development going on with HDDs - we have been stuck at 4TB for about 18 months now, and the prices are still high.
Similarly 2.5" HDDs have been stuck around 1TB for what seems to be years now - though some manufacturers are starting to offer 1.5/2TB disks. I know the 2TB disks are actually thicker though and can't fit in most notebooks. I'm not sure if that is also the case with the 1.5TB drives.
I remember reading about some new breakthroughs (such as
HAMR) that should start increasing density significantly, but nothing seems to have come of it.
In some ways, I wonder if they are intentionally holding back, the way that the mainstream projector industry seems to be avoiding LED/Laser light sources - moving to them eliminates the sale of new lamps, which probably have a good profit margin. Moving to extremely high density drives - even just a factor of 10 - would mean that most consumers would only ever need one or two disks.
In the real world though, the latest thing seems to be moving from 800GB to 1TB platters, which means quieter/more efficient drives, and the top end moving to 5TB - most current drives use 5x800GB. Though we currently we only have 4TB drives announced using this technology.
And it seems that drives using HAMR
may start to appear in 2014 - but will only be increasing density by about 50% for now.