Dictionary Reference

De los pocos diccionarios que existen con la definición de este concepto, que por otro lado califica como de "jerga".
"the gap between those who have computers with Internet access and those who do not, as well as the gap between those who are computer literate and those who are not".
http://dictionary.reference.com/browse/digital+divide
Por cierto lo he encontrado gracias a metacrawler.

y da esta otra también de
 The American Heritage® New Dictionary of Cultural Literacy, Third Edition
Copyright © 2005 by Houghton Mifflin Company.
Published by Houghton Mifflin Company. All rights reserved.

Cultural Dictionary

digital divide definition

A term that describes the division of the world into two camps, those who have access to the Internet and other advanced information technologies and those who don't. The term highlights the issue that those who do not have access to such technology are potentially destined to futures where they will be at an economic disadvantage.

Note: In geopolitical terms, the divide is between the developed and the developing nations, or, roughly speaking, between the North and the South.

Note: In domestic political terms in the United States, the divide is between educated, well-off members of society and those who are less well-off.