Microsoft’s selling Slate, its online political/cultural magazine, to the Washington Post Co. You might recall it was another WashPost subsidiary, Newsweek, which gave a “Seattle-mania” cover story to original Slate editor Michael Kinsley. Now, the site (the last vestige of the Microsoft Networks’ original “shows” content plan) will be outta here. Current editor Jacob Weisberg promises only that “for the time being, several Slate employees will continue to work from Seattle.”