Our paper forms for the 2010 census are being processed by very high speed optical scanners, which create a digital image of our forms exactly as we filled them out. Those machines also create a numeric data record that is used for the statistical aggregation of answers from all persons in the census.
One decision we had to make was whether to save both the numeric data record (for statistical purposes) and the digital image (to aid the genealogists of the future). We've decided to save the digital images and transfer them to the National Archives for safekeeping until 2082.
The blog is on the website 2010census.gov, or you can go directly to http://blogs.census.gov/2010census/