UPDATE Feb. 5, 2013: they've now changed the death date on SSDI, which feeds to Genealogy Bank. It now says Dec 14. See this for original Genealogy Bank info:
http://www.youtube.com/watch?v=EUddsWfQBbY (on-screen demo that info from SSDI is fed as Dec 13, just as Intelhub article linked shows in screenshot from SSDI). For an Ancestry.com example see http://www.youtube.com/watch?v=Fbl1w3kTTF4
The fact that it says "proved" for the death on the 13th, is important.
Yet, one thing this article does not deal with is the question of whether it is the SAME Adam Lanza -- clerical error or no, on the SSDI.
Fortunately, we have proven now that it is the same Adam Lanza.
There is an article from New Hampshire, written a little while after the shooting, which discussed a local nurse who looked up Adam, in curiosity. She found the newspaper announcement of the birth. Her cropped image from the newspaper shows the picture of the baby, the date of birth (and weight of baby), full name. And of course the names of the parents would have been given (though they're not in her cropped image from the newspaper).
So: Adam Peter Lanza was born on the same day in New Hampshire as the SSDI Adam P Lanza's age would indicate, whose state of death was New Hampshire.
For the actual proof ...
with links to the New Hampshire article and screen shots, see: http://youcanknowsometimes.blogspot.ca/2013/01/adam-lanza-is-dead-dec-13-same-adam.html )
Note: SSDI uses a double-proof provess; they require the state of death (if died in the US) to issue the forms to them: funeral homes or coroner or local registry, NOT Bureau of Vital Statistics. (To see a death cert, redacted, once it's submitted, one must have the SSN and pay a fee.)
And where are the death certs for the other dead ... ALL of them? I'd love to see those. (If it was a mix of real -- maybe mistakes? -- and phoney deaths -- planned, so there would be no deaths? -- for a covert operation.)
There was a LIVE ("active") school shooter drill nearby, not just a FEMA class on the subject in Bridgeport. Lt Vance of Newtown confirmed the live shooter drill; it seems to have been in St Rose of Lima school. EMS workers complained that there were so many people hanging around, it seemed as if it was a drill.