To c&p a comment I made on LJ:
I keep getting this feeling that the crack doesn't actually DESTROY anything, but that it rather just erases all memory of something. All the events--Cyberking, Dalek Invasion, etc.--still happened, but the MEMORY of it has been erased from human history.
This is why I think Rory isn't actually dead. I think he survived the shot. This may be over/wishful thinking, but firstly, the duration of the shot to the scientist Silurian was longer than the duration of the shot that hit Rory. Secondly, the scientist was at closer range than Rory was when shot. Thirdly, and this is where I'm stretching, it's possible that the Silurian weapon doesn't work as well on humans as it does on Silurians, just like the taser managed to kill Alaya when, most times, a human can survive such an attack.
So, I think that Rory was actually knocked unconscious, perhaps to the point of near-death, but not completely killed.
My theory on the crack is that it simple throws whatever it consumes out into either another reality, another dimension, or perhaps into various points in Time. So I bet we'll see Rory again, but somewhere else in some other time (maybe explaining the date on his nurse ID badge?).