Is a quantum jump the same as or related to what I have referred to as a "quantum leap" in the past? IIRC, a quantum leap is supposed to be when a electron changes it's orbit. Which I believe was also thought to be instantaneous?

Yes.

As for timing, it takes a few hundred attoseconds. See http://www.nature.com/nature/journal/v436/n7049/full/nature0.... Under 1 quadrillionth of a second is, for most purposes, instantaneous. Which is why you were told it was instantaneous. But it is now a measurable process.

The timescale that we are talking is what it takes light to travel a micrometer or so. Which is about the size of the smallest bacteria.

> light to travel a micrometer or so.

The Bohr radius is around 5e-11 m, while the bacteria is around 1e-6 m. That seems like a gulf of difference. What's taking it so long?

I'm qualified to quote original sources found from Wikipedia, not to explain them. :-)

That said, in the Bohr model, electrons move at around 1% of the velocity of light. Multiply by pi for half the circumference, and you're in the right general ballpark that the wave takes this long to propagate both ways around the atom and then set up interference with itself resulting in the new orbital.

(A highly inaccurate picture of what is really happening, but it gives basic intuition.)

It's the same thing.

QM dogma, from Einstein's photoelectric effect explanation, to today, has been that it is instantaneous. Apparently that explanation is now being discarded, without so much as an apology for ~100 years of misinformation, as far as I can tell.

I have a simulation of a quantum jump as well, maybe I should polish it up and get it published in Nature also.