Not really Ben/Leslie buuuuttt.....
....I know there are couple other West Wing lovers around here that I thought might get as psyched about this news as I did:
"Bradley Whitford to Guest Star!
The Huffington Post can exclusively reveal that in an upcoming episode of the NBC comedy, Bradley Whitford, who played Josh Lyman on "The West Wing," will play the departing Pawnee city councilman whose seat Leslie and Bobby Newport (Paul Rudd) are running for.
According to "Parks and Recreation" co-creator and executive producer Michael Schur, the name of the March episode ("Live Ammo") came from a "West Wing" episode, in which the character Ainsley Hayes wrote a position paper that got the president to quickly change his mind on an issue. She's shocked at the speed of the switch and the pace of the White House, and as Schur recalled, Sam Seaborn said to her, "Look, this is the White House, we play with live ammo around here."
The "Parks and Recreation" episode doesn't have the same story line as 'The West Wing' episode, "but we kept referring to that line and that idea that if Leslie were to win… when she's on City Council, her decisions have a much wider impact," Schur said in an interview on the set of the show. "So we actually have Bradley Whitford say to [Leslie] at a point in the episode, 'Look, this is City Council, we play with live ammo.'""
Source