I spent most effort in the 5 first pages, which I found very interesting. The new part for me was to read about it in the big scale. In a way I already pick up learning objects and collect them on my web site and mash them up to new contexts. In a microscopic scale compared to Downes vision.
But I do already meet the problems with the different file formats, that can make it challenging to make the different parts work together. So I have already earned a lot of benefits from the coding courses in code.org. Still have to learn to master the XML, I see now.
All in all I agree with Downes. If we really want the global benefit from openness in education it will be an advantage to obtain some sort of consensus in the use of code language, the meta data etc.