It is fair to say that the largest LMSs, such as Blackboard, could be described as Web 1.0 dinosaurs, even when their more recent releases do integrate some of the collaborative Web 2.0 technologies (such as wikis or blogs).
It seems to be the way the large LMSs are evolving, however the pace of Web 2.0 innovations is such that large LMSs may always stay a few years behind (Barbaux, 2005).
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(Norman, 2005)
References
Blackall, L. (2005) Small Pieces in elearning, Available: http://teachandlearnonline.blogspot.com/2005/05/small-pieces-in-elearning.html
Dalsgaard, C. (2006) Social software: E-learning beyond learning management systems Available: http://www.eurodl.org/materials/contrib/2006/Christian_Dalsgaard.htm
Norman, D. (2005) Small pieces Available: http://edcommunity.apple.com/adc/tools/wp-content/smallpieces.png
Wilson, D. (2007) Is LMS a corporate competency, Learning reflections Available: http://elearnity.blogspot.com/atom.xml
Barbaux, M. (2006) Is an LMS the best tool for learning and teaching? Available:
http://blogs.usyd.edu.au/ecommunication/2006/08/is_an_lms_the_best_tool_for_le.html