BICEP2

I am trying to understand the details myself. If you want hairy details, look here, here (Lubos has a guest poster), or here or here for a little more on how reliable it looks. Or have a crack at the paper yourself--I haven't finished it yet.

The coolest of the pictures show what look like twists. That's what they are. Light, being oscillating electric and magnetic fields, has a direction for the electric field and another for the magnetic field. Most of the time the directions in a collection of light are random, but you can get polarized light from particular sources, or by blocking out the polarization you don't want, and some more exotic ways.

The twists in those pictures...

You remember waves in the sea, and up and down waves on a slinky, and pressure waves along the slinky. In physics class you may have been introduced to "twisting waves" in a rod--you can't quite get those to propagate along the slinky--and not in the ocean or the air at all.

But gravity waves are different, and they can be "twisty" Please follow that link for the picture to see what a twisty wave can look like.. If, as looks more and more likely, the universe grew from a big bang, even relatively small fluctuations early on should leave some kind of imprint. Unless they've made some mistakes, they're looking at the impress of gravity waves on the universe very early on. (The pictures represent a small section of the sky.)

If this pans out, it is probably Nobel material.