AR vs. UVR?

I came across an interesting article about voter registration: "The Alternative to Universal Voter Registration" where John N. Hall strongly supports Automatic Registration (AR) over Universal Voter Registration (UVR). To people who are not election experts the distinction is a bit subtle. UVR has states proactively try to register everyone to vote, while AR has the federal government somehow use Social Security records to automatically register people.

In Mr Hall's words, AR can be implemented by doing the following:

"Computer programs read through the Social Security Administration database, extract the data of age-eligible citizens, then send that data to the states." (from The Alternative To Universal Voter Registration)

Now that I started writing this post and did some more googling I see that this is already a heavily debated topic that has flown back and forth, starting with John Fund's (of the Wall Street Journal) original talk, to Rep. Barney Frank's angry denunciation that he had nothing to do with the claims that he was involved in any way with Universal Voter Registration, to Mr Fund's retraction of the claim, to more links than you can shake as stick at about the topic.

Anyway as usual I am johnny come lately. Phew. My original thought though was about the original post. You see, John Hall, being a "computer programmer" makes it sounds simple:

"Voila! Why make mandates on all those state agencies and dragoon all that manpower entailed by UVR when a computer program can register everyone? A competent programmer could write the extract program in his sleep." (from The Alternative to Universal Voter Registration)

Any description of this that starts with "Voila" and ends with "in his sleep" is ... well let's just say, it must be a bit of a simplification....

For example I would imagine that there would be major privacy concerns about sending information out of the social security systems out to each of the states. I am not sure that the states registration records even include social security information. And what about all the voters who don't have social security numbers, there must be some, or many? And how quickly are the social security databases updated when people die?