Sometimes I think LJ has a very odd business model.
Looking at my flist, if I was LJ I would be rapidly removing the ability to repost comment to Twitter and Facebook until the code was in place to improve security on it. Not the reposting of LJ entries, just the comments. I think that may be the bit they haven't thought through too well.
Did they ask about his before they did it and I just missed it, or did they just go ahead and do it?
Although a full rollback would probably be easier until they sort it all out.