So, remember a month and a half ago when I wrote about how LiveJournal was munging outbound links? They had this horribly buggy code with the laziest-written regular expressions I'd ever seen that actually broke a lot of outbound links by trying to insert affiliate URLs where they didn't belong, in addition to the inherent evil of inserting their own affiliate URLs and hiding the fact. They'd supposedly turned it off.
Well, it's back, and it's breaking browser behavior such as opening links in new tabs again. Note that this new version actually makes the link address you copy when you right-click and select "Copy Link Address" be the munged version rather than the original link.
More info at:
Blocking outboundlinks.net and outboundlinks.me with NoScript seems to stop the evil JS for me (but possibly I just did the opt-out thing the last time around). Jonquil has some other suggestions as well, see the first link above.