12/21/2012 will have the same temporal significance as the points where all the longitude lines cross have geographically.
I'm holding out for a thin layer of galactic dust that scatters galatic light in a cross-shaped pattern while we are transiting it...
I think it will have more than that...
Longitude and Latitude are artifical lines that have no physical existance
The earth will be a big magnetic field passing through an even bigger one. I am betting the bigger one wins
while we are in the same hemisphere we are actually getting a boost from the galaxy’s magnetic field- once we cross over, who knows how long ‘til we feel a braking effect.
And even the tiniest amount will shift all that water... some place