It definitely isn't a replacement or substitute for a pyschologist or psychiatrist. I think it is a fancy name for giving advice and asking good questions.
Really, really distilled:
Psychologist - dealing with past issues and mental illness, how you feel about things
Psychiatrist - diagnosis and medication
Life Coach - learning to move forward and live the best that you can, practical things you can DO
I just thought that I've been doing this for/with friends and random strangers for 10 years! That's quite a bit of experience. There isn't any license or certification required to start. Just skype or a phone and a website.
And - I can do it when I'm depressed (this is HUGE). Not only can I do it when depressed, I get HUGE benefit out of it. Helping someone else talk through their problems will get me out of a depression every time. It would help other people, supplement my income and help me staying stable.
Hey Red :) - I hear you on trouble with traditional work! With bipolar it is hard to find direction in life, or even to find identity. Those alone make working stressful, not to mention that traditional workplaces have a lot of bp triggers!