Worse still, they (being singular where gender is indertiminate, or you seek to be neutral) is not grammatically-incorrect, and has a long history in the English language. It's a bit like the split infinitive, which is often considered to be incorrect but isn't.
The author: they really should have known better than "s/he", to boldy write for RWW.
Should a singular they be used exactly like any other singular pronoun:
"I will say of that person: they laughs a lot."
(Compare: "I will say of that person: she laughs a lot.")
"They is the person you should talk to."
(Compare: "He is the person you should talk to.")
Or should it instead be:
"I will say of that person: they laugh a lot."
"They are the person you should talk to."
Presumably if you're referring to a specific individual, you already know the gender so using "they" in that situation would appear to be incorrect.
However, in the general sense I would argue that the conjugation of verbs follows a pattern but that pattern doesn't have to be singular vs. plural. Given "he has" or "she has" one might expect a singular "they" to follow the pattern "they has". However, "I" is singular yet it uses "I have", so it's not unexpected for the singular "they" to use "they have". In other words, the conjugation of "they" is the same regardless of whether it's singular or plural.
they is used in a bunch of situations where the person prefers to be non gender specific. It only feels wrong for the first little bit, but hang out with enough people that have complex gender identities and you will get used to it.
The author: they really should have known better than "s/he", to boldy write for RWW.
Edit: Added a sourcewith examples - http://www.crossmyt.com/hc/linghebr/austheir.html and the Wikipedia page seems to have some discussion about it too - http://en.wikipedia.org/wiki/Singular_they