Also, remember that the wikipedia article is the collective opinions of everyone who participated in writing it, not any sort of authority on the nomenclature of the solar system.

As I understand it, asteroid is still a useful descriptor for objects that are part of the asteroid belt and NEAs, as it represents a dynamical grouping of bodies that share similar orbital and physical characteristics. Specific names for different groups exist, such as Atens, TNOs, Jupiter Trojans, Centaurs, etc. so it's probably best to use those descriptors, rather than the catch-all SSSB.

the term 'SSSB' replaces the outdated and confusing term 'minor planet', but does not affect the names for more specific dynamic groups.

Thus, the terms SSSB, dwarf planet, and planet tell us something about how massive the object is, from small irregular bodies, to rounded bodies, to bodies large enough to sweep out the debris of planetary formation. The specific names for dynamical groups tell us where the objects are, and in some cases where they came from or what they're made of. Planets can also form dynamic groups, such as the terrestrial planets and gas giants.

So Ceres is both a dwarf planet and asteroid, and is sometimes even counted as a terrestrial planet. Pluto is a dwarf planet, TNO, KBO, and plutino. Eris is a dwarf planet, TNO, and SDO. Both Pluto and Eris also belong to a new and unnamed group of eccentric, inclined, long-period ice dwarfs. (Wouldn't that be a fun bit of terminology, the 'EILPIDs'!)

To me, this new classification system makes a lot of sense, and avoids being extremely arbitrary. There are going to be borderline cases where it's not exactly clear which groups a body belongs to. I see those are merely opportunities to refine the terminology, and don't see why they should doom the definition as a whole.

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