"The British newspaper The Guardian solicited firsthand accounts of the blasts from those who were there. Responses poured in from people like Matina Zoulia," reports The Wall Street Journal Online.
"On Wikinews.org, a Web site that any visitor can edit, several articles cropped up, each written by dozens of collaborators, while another site began keeping a list of confirmed survivors of the blasts. LiveJournal, which provides free blogging software, has dedicated part of its site to locating Live Journal bloggers in London who haven't been heard from."
The article has lots of good links.
