When I was at MIT working on .LRN and iLearn we received some very valuable feedback early on by an MIT physics undergraduate. Her comment has stayed with me all these years: "When you design e-learning systems, don't forget that we (students) learn as much from each other than we do from our instructors." What she was describing, of course, was the power of peer-to-peer learning.
I confess I still don't understand Web 2.0. David Warlick, however, has distilled for us the difference between School 1.0 and School 2.0.
School 1.0: "Teachers deliver content and skills, students are mirrors, reflecting content and skills back to the teacher (or government). If the reflection is in the image of the teacher and the state’s standards, then success has been achieved — regardless of any continuing affects on the students abilities to prosper in a rapidly changing time. (See diagram 1)"
School 2.0: "Students stop being mirrors, and instead become amplifiers. Their job is not merely to reflect what they encounter, but to add value to it. Content and skills are no longer the end product, but they become raw materials, with which students learn to work and play and share. (see diagram 2)"