Guy Gardener wrote:
In the Supernatural Universe it is strongly suggested that that Sam Winchester played Dean in the episode where he had to abort a Universal Tour to avoid incriminating himself and what he did to pay for College.
Heh. I'd forgotten that bit of business.
As to the OP's question: the answer is, of course, the final scene of season six. I consider that scene as a huge middle finger from the departing showrunner to the higher ups -- not so much a passing of the baton, more of a hurling the baton into the thick, thorny bushes with the parting shot, "You think the show'll be fine without me? Dig it out of this mess yourselves!" So Rebecca Rand Kirshner takes over as showrunner in season seven and wastes no time in proving how essential Amy Shearman-Palladino really was to the series.
I soldiered through the final season like many die-hard fans but -- like Brian Michael Bendis once said that West Wing ended, for him, at the end of the fourth season when Sorkin left -- Gilmore Girls truly ended after the sixth season, for me.