I thought this thread died off so I was originally going to comment: "Well what'd ya know? This thread died moments before we've gotten loads more pre-alpha information."
Before making this comment, I see that now there's already posts regarding information on pre-alpha so you've read my mind!
Either way, I'm glad to see that some information has leaked, especially the loved meat game mode that's quite accessible now (but there's catches to this access).
I did not make this comment for no purpose so here is this: 
Caption: Buried's Pre-Alpha Map Layout. Originally there were meant to be 3 maps, Facility Powerplant, New York Tunnels, and Abandoned Mine.
- I assume Buried became a combination of the 2
- New York Tunnels was an inspiration map from Abandoned Mine, that featured being underground a city of some sort, which one can assume would be New York.
- Not much is known about Facility Powerplant
New York Tunnels Reference 1
New York Tunnels Reference 2