The bit everyone is theorising about is that Booker activated the biosphere and only relations of Andrew Ryan can do that. So people are coming up with theories about a relation there as this one is set earlier so he could be father or something. But I just see it as a hole
Well that would be pretty cool, though I feel like it's more likely just to be a hole as well.
Also, on a slightly un-related note, I recently took a trip to Las Vegas and visited the casinos and such. And I must say, the original Bioshock's architecture must have received some inspiration from the MGM Grand. Walking around there was so cool. I felt like I was walking through an alternate Rapture.
