For reasons which escape me, and which haven't been announced or explained, a very large random selection of users have had their birthdates removed from their user profile pages.
The LJ TOS means that maintainers of adult communities (of which I am one) have to ensure that all members of those communities are adults, according to the dates of birth shown on their profile pages. The fact that most birthdates have accidentally been hidden is a royal pain.
Check your own profile page at
http://exampleusername.livejournal.com/profile to ensure that your date of birth is displayed, if that's what you would wish. It may have disappeared -- mine had.
You can decide whether, and how, your date of birth is displayed on
this page, where a drop-down will offer you "Do not display", "Display only the month and day", "Display only the year", or "Display month, day, and year".
This has been a public announcement on behalf of the poor sods who mop up after LJ cocks up.