It may not look like much, slightly reminiscent of a 2U rackmount machine with a front panel full of drives. It is exactly that, a Blackford based 2S box with 2 internal drives on the normal SATA ports and a secondary RAID controller for 12 additional SAS or SATA drives.
The name, in violation of standard Intel policy, actually makes sense and means something. SSR is Server Storage Rackmount, 212 is 2U 12 drive, MC is McKay Creek, and the 2 is just there to satisfy Intel marketing, something needs to be gratuitous.

You can put in just about any Intel CPU that will fit in a standard mobo, and use any standard ram. It will run all PC OSes, from MeII to Linux and everything in between. It is a standard server. In addition, the SSR212MC2 also is certified to run storage oriented OSes, be they MS, Ipstor, Falconstor, Wasabi or others, allowing it to be a server or a device.
It will do all the usual tricks, RAID 0,1 and 5, plus all the normal combinations thereof. You can do RAID level migration and on the fly expansion of volumes. In layman speak, you can add drives later on to an existing volume.
For expansion, it comes with two GigE ports, two PCIe 8x and two 4x slots. If you want to add in a few 10 GigE ports, you can with standard cards. Same with SAN ports, a video card, or anything else you want, the heart of this is a standard server.
There are two SKUs, the normal Software RAID version for $2800, and one with an Intel SRCSAS144e RAID card for $3600. This card takes one 8x slot. Neither come with CPUs, you can put in whatever you want there, same with the drives.
That said, you will probably never see one for sale as a barebones, they are aimed at VARs and system builders. They exist to make a storage server offerings available to a level of white box vendors that would never have been able to play in the space before. ยต