No problem on this. I will keep it on permanently but we will track down why sometimes it resets too early or incorrectly on some users. I can duplicate it when I close all my browser windows and then reopen to the forums. It kills my last login time when it should hold the time for at least 35 minutes or so of inactivity. Technically you should be able to open as many windows as you want or even a browser on another computer and the lastlogin should be the same until a session has been started and then goes inactive for 30 minutes (or if you explicitly logout).

In the meantime this workaround should help those bothered by this until we nail it.