For a bit of fun I set up a cron job grabbing the Hacker News leaders table. After 42 days of running I pumped the resulting HTML through a little Perl script and then into Apple Numbers for some analysis.
Just picking the people who had greater than 5,000 karma on August 12, 2009 some patterns emerge. Especially the rise and rise of edw519 who is closing in on nickb. edw519 is adding an average of 108 karma points per day.
Other users who are moving fast are patio11 (adding 59 per day) and jacquesm (adding 83 per day). I don't appear on the graph because I had below 5,000 karma when I started the script.