lj2006

 lj2006  is a summary of how LiveJournal switched from users at paths to users at subdomains due to various security and other reasons.

Articles
The story is fairly clear from these three posts. Note how many comments there are.

Changes to User Subdomains Krissy (ljkrissy) 2006-01-19 02:47:00

Discussing The Security Changes David Recordon (daveman692) 2006-01-26 16:36:00

 the XSS security challenge Brad Fitzpatrick (bradfitz) 2006-01-30 22:18:00