The status indicator actually meant something when you had to "sign on" and "sign off." You were available; tying up your phone line. Now I don't trust the green bubble with availability with modern messengers. Maybe they just turned on their phone for a minute to check a post/email and are busy again. So I ignore it mostly. ~ I remember setting special alerts for people when they would sign on, setting schedules explicit or implicit to talk to people. Maybe we need to revisit how to intentionally capture presence in our messengers.