Martin Weller raises several points to support the use of a combination of Web 2.0 type tools, rather than an Institutional VLE. While I think that the points he raises are valuable, and that the combination of tools would make a good set (call it a PLE or not as you like!). I agree with many of the comments, however, that it’s just not going to happen in the next few years. He’s also posted a follow up post, answering several of the points that people raise.