Yeah, there are different versions... and I could be wrong. I gave the high school one since it's what I could remember off hand. Getting a "D" was just as bad as failing though.
In some places, sadly, getting a low B is considered 'failing'... In most of my classes, at least. But I suppose the pressure gets you to work more quickly and efficiently.
In grad school, we were specifically told not to get too many A's and to focus on publications. If some industrious type got mostly (or all) A's the next question from their committee was: Why aren't you working on publishing?
C's though were failing. Still, you had to try really hard to fail. The B's were inflated.
The difference is probably domains - a Ph.D. in cognitive neuroscience doesn't prepare you for much else than doing science. There, judgment for a tenure-track job begins and ends with publications. And no one will want to see grades and no CV ever includes them.
Computer Science is no different in terms of criteria for a tenure-track position. Well, publications is only half of it, grant money is the other half, but I imagine that's true for your field as well.
The CS departments I've been a part of don't expect students to publish much - if anything - until after most of their course work is done. That's usually about two years.
I think it depends a lot on the school or the department.
When I was in grad school for physics, C+ was considered failing. Beyond that, we were specifically told, as long as we passed, grades didn't matter. It was of course quality of research that mattered.
I don't know how differently people faired with different GPA's coming out. I think employers mostly looked at publications and references. And I'm not far enough out to say who was "successful" yet.
The first CS department I was in didn't have quals. You had to maintain a 3.7 GPA over all course work to be admitted as a Ph.D. candidate, so grades did matter.
I wish I had started out in departments like some of you described. I started doing research my first year, and my grades suffered for it. I got three of those Bs, and I had to take an extra course just to be admitted as a Ph.D. candidate in that program. Luckily, I have since transferred to a different school.
