There's a new introduction and one chapter added at the end, otherwise the text seems identical to the original (though I only read it once about 8-9 years ago, I don't own a copy of the first edition). There are lots of colour photos and scans of documents that weren't in the original and the version I bought from the publisher came with an extra book of essays and interviews from the scene and its peripheries (which I'm going to start today).How up to-to-date has he brought it? I heard that he fell out badly with david tibet, but maybe thats not true...
I don't know anything about Keenan falling out with Tibet but Keenan seems to be done with the subject. I know he ebayed all the stuff Coil gave him as reference material for the book (lots of albums signed and dedicated to him) which I always thought was odd.