Individualized Education Plans

I Speak of Dreams links the concepts of the Personal Learning Environment (PLE) with Individual Education Plans (IEP) and Personalized Learning Plan (PLP) in her post about Differentiating Education. IEPs have traditionally been used for special-needs students, but she points to a charter school now offering/requiring a version of them for every student -- and really, why shouldn't every learner have an individualized plan for what they're going to be learning and how they might do that best?