Here's the post:
Regarding the Incident from December, 1
Dear LiveJournal users.
Yesterday, some journals had 3rd party content published and reported, immediately a security response team started reviewing the incident and taking required action.
We are currently reviewing user security as a precaution and will follow up with any findings and potential recommendations soon.
Livejournal security and privacy remains a priority and our security team continues to improve your blogging platform and prevent abuse of Livejournal.
Further updates will follow but at the present time our priority is finishing the review.
Users are reminded to keep passwords secure and as a precaution we recommend a password change ASAP so new password strength requirements (deployed 10 months ago) can be applied to all user accounts
No further details yet, but you may want to take the advice and change your password anyway.