ISP blocked due to abuse?

Well, it seems today that I'm now unable to post anything over at the 4chan imageboards, otherwise I get this message:
"Posting from your ISP has been blocked due to abuse. [More Info]"
I can still browse the site, all the images and threads load fine, I just can't post. What gives? I've never posted spam or porn.

The "posting blocked from your ISP" messages that everyone was seeing earlier were a glitch. Everything is fixed now. (There are still a handful of blocks in place, but an error caused *everyone* to be blocked.)