|Pie Town, New Mexico in the 1940s|
The National Archives and Record Administration (NARA) will publicly release the 1940 Census records on April 2, 2012.
The 1940 Census will be available online. But it won't be searchable by name, at least not at the outset. Scuttlebutt has it that the National Archives will eventually provide name search capability. Even if they don't, I'm sure Ancestry.com will have it up and running in fairly short order.
But for starters, the only online option is to browse the 1940 Census according to what the Census Bureau calls enumeration districts, which are essentially the territory covered by a single census taker. If you know a person's address in 1940, you can figure out their enumeration district and peruse the relevant Census forms.
It's not necessarily easy, but it's not too difficult either. NARA has a detailed set of instructions for locating the 1940 enumeration district using Archive records. They also offer a description of the information available from 1940 Census forms, along with a page of FAQs about the 1940 Census.
Steve Morse, one of the gurus of online genealogy, has created several helpful online tools for tracking down the proper enumeration district.
I hope your breath is appropriately bated, as this will be one huge new data source for family history researchers.
Don't forget to also check for your family history at Ancestry.com and NewspaperArchive. These are subscription databases, but they are among the most powerful research tools available for looking into family roots.