At many previous times, on days when important, influential or otherwise respected persons have died, the site turns the header bar (normally orange) black, as a mark of respect.
I dunno, I think Richie was appropriate, and maybe Jobs, simply because, like him or not he was a great notable. But an actor? That just doesn't seem right. The black bar should recognise significance in computing, I think.
No offense to Nimoy of course; the guy was an iconic actor and personality. But, as Spock would note, his passing is irrelevant to computing.