I'm using Firefox on two different PCs, one running Windows 7, the other running Vista. They're both still requiring me to log in every time. I cleared cookies for Exilian on the Vista PC (but not the other one, as far as I remember) at the weekend, but it should have re-created one by now, surely. Safari on my iPhone seemed to get really confused about whether I was logged in around the weekend as well, but has now settled down again, leaving me logged in all the time. I'm pretty sure there wasn't a Firefox upgrade at the weekend; maybe some other component has changed without anyone knowing? Anyway, it's an irritation rather than a significant problem, and it will probably go away as mysteriously as it appeared.