(timings are approximate)
Hour 0: news is created/disseminated from the source

Hours 0-30: people with a direct interest micro-blog (Tweeting, fb-status, etc.), text, and blog about it.

Hours 12-48: people with a secondary interest micro-blog, text, and blog about it.

Hours 24-72: dinosaur print and broadcast media start to disseminate the story.

Hours 48-144: people who prior to 2001 thought  "computers were for geeks"  and people under 21 who would have been in that camp if they were old enough start to micro-blog and e-mail each-other at work about it, sharing links to print and broadcast media web sites ad nauseam and posting insane rants in the comments sections off the news stories and in unrelated forums before getting distracted by the next story.

Oringinal post: http://mbarrick.livejournal.com/961804.html