Constance Potter wrote an article on the 1940 about the new questions on the 1940 census. Her article was included in the 2010 winter issue of Prologue found on the NARA site. http://www.archives.gov/publications/prologue/ It is a great read for this census.
One set of questions enumerators asked concerned the type of home you lived in. It included information about the number of bedrooms, the number of baths, if it had running water, how it was made, and if you had a radio. Sadly this part of the census was destroyed.
Another set of questions asked were about infant children. Yes, they were destroyed too.
The detailed questions asked in this census are extremely useful. Questions about the highest grade you attained educational and what type of work you do were asked. Information about immigrants and whether or not you were receiving a railroad or social security pension were asked. The best question of all is where you were living on April 1, 1935. I wonder if my gr-gr-grandmother will show up on this. She died in November of 1939 and was living on April 1, 1935. It would be interesting if her information was supplied! You never know!
Be on the lookout for more information about the 1940 Census!