Khan Acadamy

Was just watching 60 minutes and saw something that blew my mind.
I don't know if anyone else has heard of KhanAcadamy but I think we could be onto something here.
Here's the link: http://www.khanacademy.org/
Watching the interview with Sal Khan, who started it all, I could hear my own beliefs about education. Sal began posting online videos to help a relative with some school concepts they were finding difficult.  This is where the online classroom idea began. Sal began creating videos that cover a huge amount of topics from basic addition to Astronomy.
What struck a note with me though was not the incredible amount of published content that I could use in my classroom, but what Sal was saying about teaching. Sal believes that this could be used to help  the kids who are struggling with some concepts. The children can work at their own pace to fill the gaps they might have and then move on to the next concept when they are ready. The same goes for the children who are racing ahead of the others. It doesn't seem fair for them to be limited by what their class understands. It can be like having an extra teacher in the room to help explain some concepts to the children. Each video then gives the children an opportunity to practice each concept. The children can learn at their pace and can have content covered as many times as they need.
The only problem I see, is that the lessons don't use the numeracy project strategies, so could be a little hard to use in a primary school in NZ.  I see this as a useful tool to extend GATE students further. It can also be a great tool for intermediate schools. Would be interesting what teachers in NZ make of this. What do you think?