Some of these provide a good example of why context matters, for example they identify one of the non-peer reviewed documents as an article from Newsweek written by Peter Gwynne. How does the IPCC use this document? They use it as an example of early work published in the media which later turns out to be wrong. To quote from the report:
Not all theories or early results are verified by later analysis. In the mid-1970s, several articles about possible global cooling appeared in the popular press, primarily motivated by analyses indicating that Northern Hemisphere (NH) temperatures had decreased during the previous three decades (e.g., Gwynne, 1975).Other non-peer reviewed sources are books (very few books are peer reviewed) or the proceedings of workshops which are non peer-reviewed but usually provide the very cutting edge of the science.
However, while it would be amusing to look at the the details of the assessment, it is all moot. The key point is that the IPCC does not claim to use only peer reviewed literature. This is clear from the document Procedures for the Preparation, Review, Accpetance, Adoption Approval and Publication of IPCC Reports in which Annex 2 specifically deals with how to use non-peer reviewed material. To quote from it:
Because it is increasingly apparent that materials relevant to IPCC Reports, in particular, information about the experience and practice of the private sector in mitigation and adaptation activities, are found in sources that have not been published or peer-reviewed (e.g., industry journals, internal organisational publications, non-peer reviewed reports or working papers of research institutions, proceedings of workshops etc) the following additional procedures are provided. These have been designed to make all references used in IPCC Reports easily accessible and to ensure that the IPCC process remains open and transparent.So to the group that claims that the IPCC is invalid because not all the material in it are peer-reviewed, I give the grade (to quote another blogger) Epic Fail.