How does the new planet definition affect the other "planets" that were being considered?

Question

I'm talking about Charon, Xena and that large hunk of rock, I think it was called Ceres. What is Xena now? And if Pluto is a dwarf-planet, what is Charon? A dwarf-moon? Is Ceres back to being just a wayward asteroid? I'd really like to know. Links with more information along with your answers would be extra helpful and more likely to gain you 10 points...thanks!

Answer 1

Pluto and Ceres are both dwarf planets. Charon is a satellite of a dwarf planet. Xena's status is undetermined until someone makes a convincing argument (or resolves its disk with an image; this might have been done. I don't know) that it is spherical. It should be, given how bright it is (which implies a certain size and thus mass) but it is an IAU comission that needs to be convinced.

Here is the text of the adopted IAU resolutions 5A and 6A. You can read them and also 5B and 6B (which did not pass) at the link below.

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RESOLUTION 5A
The IAU therefore resolves that planets and other bodies in our Solar System be defined into three distinct categories in the following way:

(1) A planet1 is a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighbourhood around its orbit.

(2) A dwarf planet is a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape2, (c) has not cleared the neighbourhood around its orbit, and (d) is not a satellite.

(3) All other objects3 orbiting the Sun shall be referred to collectively as "Small Solar System Bodies".
. . . .

IAU Resolution: Pluto

RESOLUTION 6A
The IAU further resolves:

Pluto is a dwarf planet by the above definition and is recognized as the prototype of a new category of trans-Neptunian objects.

Answer 2

the notion of "dwarf planet" doesn't exist anymore. Pluto and charon are "small solar system bodies" as are all the things you quoted in your question

PS: forgot the source you asked for. here you go.