I can't find the post I was looking for.
It was written by a physicist I read. i'm still looking for it, but there were two interesting assertions. One was that "time was not real", the other was that entanglement is deeper than time.
He was being coy, but this is what I think he meant.
By "real" I think he meant "fundamental". So time is real enough, but if we really understood it we'd see it as emerging from other processes.
It's easy to understand this with "pressure". Humans presumably named the "wind" more than a hundred thousand years ago. Much more recently humans named "pressure" as the expansionary force of a heated balloon. Pressure is certainly real. It's not fundamental though. Much more recently humans figured out that "pressure" was the outcome of atoms in motion. Atomic action is more fundamental.
I gather time is thought to be like that -- an emergent outcome of something more fundamental.
So why should entanglement be the key to understanding time?
Well, physicists think quantum entanglement is very fundamental. It's close to the machinery of reality.
Entanglement is weirder than I can imagine. If I understand it correctly, one could (in theory) separate two entangled particles by a billion light years, measure one a "millisecond" apart (a very squirrely concept in this context), and find the measurements were correlated -- even though a light signal would take a billion years to cross that gap.
In other words, "entanglement" may take place outside of time or space. That's kind of interesting. So if you want to probe time and space, and expose its underlying reality, you might as well start with probing entanglement. If you get it right, you might be able to understand entanglement outside of time (and space), and also understand why we are inside of time.
I really do need to find that post ...
Update 9/1/11: I haven't found that post, but a subsequent Carroll essay suggests I'm not just making this up.