Tonight’s the night, friends of the Upper East Side’s ruling crowd. Gossip Girl’s 6-season run is sadly coming to a halt, but before the momentous two-hour episode kicks off and we regrettably have to bid adieu to Dan and Serena (will they get together?), or Chuck and Blair (will they finally tie the knot?), let’s take a look at the way their impeccable style has evolved throughout the years. Headbands and all.