C'mon, "no idea"? There are three mentions of Andy Grove on the front page right now, and there's been at least one the entire time that the bar's been up.
Regardless of what you say it's not obvious... If it was there wouldn't be this thread.
I am aware of what the black bar represents however it is not always consistently used. for example, Ian Murdock who I consider to have a great impact on GNU/Linux in general was not given one after his passing.
The black bar is an admin/moderator decision, and because it's not applied to all front page deaths, it's hard for headline skimmers to associate the black bar with a consistent pattern.
That is why the black bar confused me - it's when the black bar isn't there that throws me off, because it makes me doubt the assumption that someone died.