Ok so since I'm not running out of the office I'll explain more:
A thread was posted in IAMA in which the submitter claimed to only have 51 hours to live. Basically he claimed to have cancer and was getting the plug pulled by his own choice. The thread received an amazing outpouring of kindness and support.
After some people pointed out holes in the story, this Gawker editor stepped forward. So either he was pretending to be a cancer patient, or he's claiming the role for some bizarre reason.
The 'witchhunt' tweet refers to an event where reddit didn't graciously accept a post asking for donations to a charity. I dont know the exact details behind it, but in the past people have posted stories about their fundraisers that have turned out to be scams. In this situation then, it's justified to question the submitter and confirm the story. Hardly a witch hunt.
tl;dr:
Gawker editor poses as a dying cancer patient to prove reddit is terrible. Reddit really just doesn't like being scammed.
edit: forgot to link to the official reddit comment on the issue!
http://www.reddit.com/r/reddit.com/comments/g14ed/i_dont_expect_anything_less_from_good_ol_gawker/c1k69fz