Following on from all our VLE discussion, this post from Scott Wilson caught my eye. He has another good diagram (I've borrowed his Future VLE one before - with acknowledgement Scott!). I have had my reservations about PLEs, and particularly how they interface with the institution. I like the idea of assembling your tools over time, but there are some real issues about how these interact with institutional systems (authentication in particular - are you a student on this course, what support do you have, how do we verify course records, etc). Scott goes some way to addressing these. I think a telling quote is:
Originally I thought that a personal system could manage all the variety of all connected institutions, but more realistically there does seem to be a real need for a more concrete coordination system sitting between the personal system and the enterprise, for handling jobs such as initial rendezvous and peer association.
Scott suggests a course coordination space where some of this is sorted out - maybe this is similar to my concept of the educator choosing loosely coupled systems. The danger is that maybe too much time gets spent in coordination for every course - which may make the default option of the VLE seem attractive. The response could be 'sure these other tools are better, but we spend the first two weeks of every course thrashing out what we are going to use. The VLE tools are good enough.'