A happening corner bakery can spruce up a neighborhood better than swaths of daffodils in the traffic medians. Since springing up two years ago, Sweet Adeline has transformed its South Berkeley block, and not for the pastries alone. Sure, owner Jennifer Millar’s Midwestern-style pies and tea breads eat like a sustained, vanilla-scented exercise in neighborhood outreach. But the sweet-natured staff and easygoing table vibe have made Sweet Adeline a de facto community center. Of course, killer buckle doesn’t hurt. The puddinglike cake with the sweet, Victorian-sounding name might have chunks of nectarine sink into its cool, pale crumb. Try any pie in the case: Rhubarb has a thick, shaggy crust and an old-fashioned burr of cloves in the filling, while lemon meringue has stiff, brown-sugar billows over smooth curd that contains a postmodern blast of supertart citrus. Urban revival has never tasted so good.