Gosh.. It seems we've got a serious Apple fanboy here -.-
Most people having issue with their MBA SSD had 128GB model and most of them are made by Toshiba.
Well this issue is basically divided into 3 symptoms.
1. SSD not being recognized at all
2. SSD is only recognized as 32k Sandforce controller
3. SSD is being recognized and partitions still shows up but facing disk failures and not being able to boot the mac.
Whichever one it is, it is basically same problem. The SSD has failed. And most people reports it's from same part which is 128GB Toshiba SSD.
The update mentioned before in this thread (MacBook Air Flash Storage Firmware Update 1.0),
seemed to be out to solve this problem but it couldn't. Now this update is pulled out (guess why?) so you can't access the page but if you search it using google and look at the cached page, it shows the content of the update. It says:
"This update is recommended for MacBook Air (mid 2012) models. This update addresses a storage firmware issue that, in rare cases, may cause a system to fail to recover from a crash.
Warning Text:
Your MacBook Air requires this update.
The power cord must be connected to your MacBook Air and plugged into a working power source.
Back up the data on your MacBook Air flash storage to an external disk or Time Capsule before installing this update. If you've already backed up your data, click Install Update to begin the update.
Do not reset, shut down, or turn off the power to your MacBook Air while updating your flash storage. If there is a problem during the update, your flash storage may become unusable and all the data on it could be lost.
When the update is complete your MacBook Air will shut down. Wait one minute before restarting it.
Boot ROM or SMC Version Information: After the update, you will have Revision TPVABBF0."
The symptom mentioned in the update is exactly what we faced. (System crashed, not recoverable, so force shut down and the question mark folder appears!) And the firmware version with revision TPVABBF0, would be for Toshiba ones unless the SSD from Samsung or Sandisk shares the same revision. (I strongly doubt so)
If you just simply say 'speculation', well, this 2012 mid air has more people with having issues with its SSD compared to other versions of MBAs and most people had same parts.
I don't exactly know how many percentage of people having the 2012 MBA with Toshiba 128GB SSD has SSD failures, but what I can say, is that it is not a usual case. I had this problem, two of my friends who bought this MBA mid 2012 because of me had same issue-.- I have never seen such issue that was this common among my friends who are using same devices. (Well, except for buttons for iPhones and iPod Touch) And I found this thread having exact same experience. Need I say more?
I would like to ask Apple about this issue but Apple would never tell you the truth. Apple would definitely avoid recall.