I want to share this link I found about LiveJournal, but I'd assume everyone's seen it already. Forgive me if I'm being redundant.
SFGate's Culture Blog (one of SFist's Johnny-come-lately rivals (I prefer "nemesis" to "rival" but wasn't sure how to pluralize it. Nemeses?)) had an interesting post about a study that graphs the moods of Livejournal bloggers by the language they use. Read it here.
Or just tell me that you knew all about the Moodgrapher already.