How to tell if someone is online?

[flowerfreak5]

How accurate is the 'user status' and 'last spotted' thing?

[Xaidread]

User status is something people can set themselves. I've a neofriend who's been offline for about two years, but her status is online and eating or something like that.
Last spotted means the days they've been offline. Less than one day means that they've been on the site less than 24 hours ago.