Right now, I am listening to Geoff Nunberg's essay (aired Tuesday on NPR's "Fresh Air") about Lynne Truss' "Eats, Shoots & Leaves." (This book is still floating around best-seller lists.)
It's about five minutes long.
There's not so much there that hasn't already been brought up here. However, he did mention the harsh reviews from Louis Menand and Edmund Morris. And he does some criticizing himself: He calls Truss' own punctuation "alarmingly insouciant." And he says she uses semicolons like he scatters fennel seed while cooking -- "in the vague hope it will somehow pull the other ingredients together."
UPDATE: The essay can be found on Nunberg's site here. Be sure to check out the notes section, where he breaks down some semicolon misuse.