Does this mean some bits of earth slide into an empty pocket, thus making the surface area smaller? Or did it just shudder back a bit in its rotation? In other words, 3 microseconds a year, or just a one-shot deal?
musta had a significant chunk-o-mass move a little closer to the earth's core. Assuming that nothin' moved out further as a result, and using conservation of angular momentum, we just speed up a little. Just think of a figure skater spinning....when she pulls in her arms she rotates faster.