It changed everything for the Thunder, the Houston Rockets and any and all players involved in the blockbuster deal.
A change of scenery has allowed Harden to blossom into a top 10-caliber superstar, eased any burden that was once upon Jeremy Lin's shoulders and left the rebuilding Rockets contending for a playoff spot.
Subsequently, Harden's absence has left Kevin Durant and Russell Westbrook balling, Kevin Martin smiling and Oklahoma City as a more formidable entity as a result.
And yet, that's barely the beginning. As I said, this swap changed everything for both teams.
Now it's time for us to see just how much.
*All stats in this article are accurate as of December 27, 2012.