Also see Language log, which has many posts on the wrongness of S&W.
EDIT: If you're not familiar with Pullum, he's the co-author of the Cambridge Grammar of the English Language and probably the most respected grammarian alive today.
I found the comment section on the NYT blog more intriguing than the article.
The arguments brought forth by Pullum (I don't appreciate your appeal to authority) are completely ridiculous, examples:
> .. both authors were grammatical incompetents.
There are many ad hominems of this kind in the article.
> No force on earth can prevent undergraduates from injecting opinion. And anyway, sometimes that is just what we want from them.
Whether you should write subjectively surely depends on the type of text that you are writing. Providing style advice based on expectations of which urges undergraduates can't resist is laughable.
> "There were a great number of dead leaves lying on the ground" has no sign of the passive in it anywhere.
The book does not claim that this sentence is in passive form at all: "Many a tame sentence of description or exposition can be made lively and emphatic by substituting a verb in the active voice for some perfunctory expression as there is, or could be heard." (cited sentence follows)
Pullum also cites three works of literature from around 1900 that do contain the phrase none of us exactly once (?!) followed by a plural verb to make the point that none of us should be followed by a plural verb.
> "The copy editor's old bugaboo about not using \"which\" to introduce a restrictive relative clause is also an instance of failure to look at the evidence. Elements as revised by White endorses that rule."
I don't know where he found that rule; my edition of the book does not contain it.
For that article Pullum gets no respect from me. He set out to bash the book and its authors with ad hominem arguments, falsifications and far-fetched proof.
You asked for sources for an opinion on a subjective topic, you're not allowed to pull the "appeal to authority" card for being given exactly what you asked for.
Could you provide an example?