I think that we are talking about the flash storage on Mac ( specially on the mac retina so I just want people to use the same term use by apple ) see tech spec from apple description. the Retina Display like the Air is base flash-based architecture.
you can understand better that for RAM we are talking about 1600Mhz. and for the flash storage I read somewhere that is up the 500mb/s. data transfer.
MacBook Pro with Retina display uses one of the fastest memory technologies available today — 1600MHz, Double Data Rate (DDR3L), synchronous dynamic random-access memory (SDRAM) — ensuring that the Intel Core i7 processor is constantly fed with data without wasting clock cycles.
http://9to5mac.com/2012/06/18/on-the-new-15-inch-macbook-pro-with-retina-display-review/
2.6GHz quad-core Intel Core i7
Turbo Boost up to 3.6GHz
'''8GB 1600MHz memory'''
'''512GB flash storage1'''
Intel HD Graphics 4000
NVIDIA GeForce GT 650M with 1GB of GDDR5 memory
Built-in battery (7 hours)2
Tel me if I'm wrong.
Thanks for the link really interesting.