Neat question Bernie, I'd be interested in a summary of what you find. It seems like the 1990s rhetoric of the digital divide and access is dying (in the U.S., not worldwide). I'm more concerned about types of participation being unequal. One paper I like that may be of interest is Eszter Hargittai's "Whose Space? Differences Among Users and Non-Users of Social Network Sites". It looks at how differences in race, gender, and ethnicity influence participation. It's not about motivation--which your question asks--but the Discussion section does look to explore some of the findings towards this end. http://jcmc.indiana.edu/vol13/issue1/hargittai.html -- Human-Centered Computing College of Computing, Georgia Institute of Technology www.cc.gatech.edu/~yardi