Both cracks are connected to Amy. She caused this crack when she decided to abdicate the starship.

@Eliott
Thats actually good thinking! Its very possible…

I think it might have something to do with the daleks

Prisoner Zero asked the Doctor if he knew where the cracks in the universe came from, which pretty much makes the mystery bigger considering he doesn’t know. Also, the zoom in made things even more mysterious!

The Pandorica appears to be the mysterious puzzle box in the finale, so I’m thinking something to do with the Cybermen. And, I’ve got nothing for silence.

Maybe the cracks could be connected to the Medusa Cascade the rift in time and space

I think the pandorica will be the puzzle box (as TE said) and the silurians will break through it. I don’t know about anyone else but I’m thinking the silurians will be the classic monsters in finale this year so its bound to include them.

Don’t ask me why i think this but I’ve got a feeling “Silence will Fall” will mean everyone will lose their voice. maybe, again, something to do with the puzzle bix. just a theory anyway

Its the Pandorica ‘cracking’ open

I think that throughout this series, the doctor is detecting these cracks from the TARDIS (because at the end of “The Eleventh Hour” the same shape as the crack appears on the TARDIS screen) and is following the signals. I think that’s how the daleks and cybermen return. Also I think the Pandorica is a superior version of these cracks and that something dangerous will descend from it.

“silence will fall” i think it means everything in the universe will be destroyed leaving only silence

If the Cybermen are coming back, where are they coming from? The Cybermen appearing in the trailer are from the other world where Rose is currently stuck. To get from one to the other, you have to cross the void. So, if they are those Cybermen, are the cracks, the void repairing itself? The Daleks are from our universe, so the connection is vague. The Silurians are from Earth and have only ever wanted their planet back, so the connection is vague as well. What if this has been caused by the Doctor? What if Amy isn’t human after all?
Failing all that, this is Stephen Moffat, so it could be anything.

the cybermen cant be from the void because when davros came back and the walls of the universe broke down everything in the void was destroy so the cybermen didnt come from the void

in the episode silence in the library the woman river song, it said she was coming back but wat could she have to do with this?

Maybe, all the monsters coming back that have all been destroyed are getting through the pandorica crack. And throughout the series it will get bigger! Cos Episode 12’s title is rumoured to be: The Pandorica Opens, meaning it finally opens completely and everything gets out!???

However, I hope that everything I have just said is untrue as I don’t want to have cracked the mystery in 2 episodes

Remember the saying from Silence in the Libary … “hey who turned out the Lights”. Maybe the Silence that is coming is connected to Lights going out as in “End of Universe”

As for the Crack, it could be a red herring.

the cracks seem to be following amy pond. maybe?

Pandorica sound similar to pandora if you know the story and also the cracks could have been put there to lead amy to the doctor or somthing perhaps river song has somthing to do with it
also arnt cracks in the fabric of the world getting old …..cracks allowed the doctor and rose a mickey to giro the parrall world then some more were made by the void ship allowing the ghosts of cybermen to come through to our world…. The toclafane defended through a crack in time and in series four finale every dingle universe would crack and shatter but was stopped sealing rose In again …you see
also disappointing that the story arc is so obvious thus year

like everyone else the “Pandorica will open, silence will fall” Line is still elusive, the breif from Radio Times (dated 03/04/2010 to 09/04/2010) for Episodes 12 & 13 reads: “A message on oldest cliff-face in the universe, a puzzle box opening from the inside and a love that lasts thousands of years… The fates are drawing close around the TARDIS – is this the day the Doctor falls?” so maybe there are clues that can help (The Love of thousands of years coul be The Doctor & River Song as no amount of time was mentioned of her travels) but I have a theory about the Cracks (And sorry if someone else has posted this already) – They somehow link with the Time Lords attempt to reassert themselves in the universe in “The End of Time, Part 2″ i say this as the thing that Prisoner Zero says seems to imply the Doctor should have Known why the Cracks existed…

Interesting that the crack in Amy’s wall and in Starship UK were the same shape as the line that appeared on the screen in the Tardis at the end of “The Eleventh Hour”.

I don’t think the cracks in the universe can have anything to do with the Silurians, since the Silurians are natives of planet earth, just as much as humans are. S I would have thought the Silurians (as in the classic series) will come out of their hibernation in an underground cave system.

I tend to agree with Martin’s post above, and think the cracks might be connected in some way to the Time Lords and the Time War, although I doubt it will be directly related to events in “The End of Time, part 2″. The cracks could even be a result of something the Doctor has done himself, perhaps. Also, the puzzle box sounds like something “The Trickster” from the Sarah Jane Adventures might have something to do with, so could the Pantheon of Dischord be involved in some way? No doubt we will get a clearer idea as the clues develop throughout the series.

“Pandorica” = puzzle box = Pandora’s box? Something that really, really, really shouldn’t be opened.

That’s my theory.

also I don’t think the cracks are following the doctor like the other arcs but more amy.