I'm confused. If the definition is:
“a celestial body that is in orbit around the sun, has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a ... nearly round shape, and has cleared the neighborhood around its orbit.”
Then what does the overlapping orbit have to do with it?
Pluto is automatically disqualified because its oblong orbit overlaps with Neptune’s.
Is that because it hasn't cleared Neptune from it's orbit? I think a better explaination is in order.

It was unclear how Pluto’s demotion might affect the mission of NASA’s New Horizons spacecraft, which earlier this year began a 9½-year journey to the oddball object to unearth more of its secrets.

Yep; the science of Pluto isn't valid anymore.

Charon, the largest of Pluto’s three moons, is no longer under consideration for any special designation.

Is Charon still considered a moon if Pluto isn't a planet? Is there a definition of a moon? (that'll probably be the next controversy)