Forget about iPad mini. What is Fusion Drive?

Apple just released iPad mini today, but that's not what's interesting to me.  Apple also released the new iPad and iMac!

First of all, not sure why people wants to purchase iPad mini besides the portability.  The price is only AUD $170 cheaper than the iPad.  Its screen is smaller and has no Retinal display; it also has a slower process.  Why?

The new iPad will be up to twice as fast as previous one as it's powered by new processer, A6X.  The wi-fi speed will be twice as fast as older model, too.  Again, why iPad mini?



Anyway, what draws my attention to is the new iMac.  Along with an incredibly thin display, it has a new hard-drive system inside its tiny box incorporating solid-state and traditional disc systems, called Fusion Drive.


What is Fusion Drive?  Not much was disclosed from the keynote.  128GB SSD + 1TB (or 3TB) HD, Fused into a single volume, works automatically...  There are speculations on how it works.  Without knowing in details, I am not sure I would opt for this option.  My thought is that having two drives: one SSD and one HD.  Installing/storing all apps on SSD and having most data on HD will do just fine or maybe better

Arstechnica has an article on some speculations on how it works.