Is "now" the bounding edge of the universe in the time dimension? The universe is expanding in the 3 spatial dimensions, could it not also be expanding in time dimension. In other words, are we stuck in 3 dimensions because we are riding the "bow wave" of the big bang in the time dimension, stuck on a 3d plane perpendicular to our world lines in spacetime? Think of a 3d-printer, are we on the upper surface of the printed object with new time being added continuously.
Would this mean that the quantum foam is the moment when the universe comes into existence, that the collapse of wave functions is when probability becomes reality? In that way there would be no need for the many worlds interpretation of quantum physics. Ahead of now is "outside" the universe i.e. there is nothing so the extra quantum states never "existed" in any sense, they were only ever mathematical probabilities. The act of observation is simply being in the now and that's why quantum systems are different depending on where you measure them - it's a different locus of the 3 spatial dimensions and "now".
Update
I don't believe that this is a duplicate question. After some discussion elsewhere it turns out that what I am describing is the Evolving Block Universe. It is well (and more formally) described by South African cosmologist George Ellis in this paper:
http://arxiv.org/abs/gr-qc/0605049
There is also a YouTube presentation, recorded in 2012, here:
http://www.youtube.com/watch?v=It6Me78dal8
 A: Note: I am not allowed to write comments yet, so I have to post this as an answer.
Besides of John Rennie's formal objections to the
concept of expanding time (at "Does time expand with space"),
I still like the explanation of the quatum physical state
of superposition that is provided with your question:
The idea that i.e. the interference pattern which shows up
within the double slit experiment is not the consequence
of different possibilities that are somehow happening at the same time 
but the consequence of a quantum physical event (the photon's path through the double slit) being beyond the realms of time and therefore only existing as its mathematical probabilities.
To stay within the framework of your thought and by using your analogy
of the 3d printer it could also make sense to assume that the time is printed out
in discrete portions, chronon by chronon. Then the single quantum physical event might be beyond time because it's too small to absorb a whole of those elementary time-units. This is only until the event gets observed, because then the event becomes a macroscopic event, which spans across lots of time units, which means that the event is not longer beyond time but - as you called it - "in the now". Hence the wavefunction collapses.
