"A flashback to Buffy's final speech to the Potentials reveals that Willow is channeling the essence of the scythe in order to activate Potentials all over the world. Defying the tradition of only one slayer per generation, Willow's spell will raise an army strong enough to do battle with The First."
From Wikipedia's entry on Buffy Season 7, Episode 29.
It's amazing that wikipedia has an entry for each individual Buffy episode. And there's the power of it in action. Wikipedia and librarything, del.icio.us-- it's activating all the librarians in the world. We're defying the tradition of an MLS (or MS, LIS in my case). I'm totally going to watch all the seasons of Buffy again. It's been almost an entire year since the last time I saw all seven seasons.