I just happened to see this thread just now....this has happened to me twice also, with two different user names from my home netbook computer. It's been a couple of weeks though.
Paul:
Happened to me just now.
Hadn't logged in but just used the bookmark on the laptop from home.
Didn't think to try to post something under the name that came up, just logged out and logged in under my name.
My user name starts with "i" and the name that came up started with "j".
I don't know if this is the same thing but the other day I came to the site and it said "this IP address has been banned" but once I signed in everything was fine.
This just happened to me for the first time. It showed me as logged in under someone else's name, but when I clicked on user CP it asked me to log in. Just FYI, it's still happening.
Hi good morning, I logged out last night. This morning when I opened my 'bookmark', I was on someone else's account. I deleted my bookmark, restarted safari, and the same thing happened again. Then I logged out the person, and logged myself in.