For a 'law' it can be trivially dis-proven. "Is water wet?". I think the article raises some legitimate questions about Windows 8 that can't be as flippantly dismissed as your analysis of the punctuation suggests.
This doesn't disprove the adage as in practice no one would write a headline or a HN submission link entitled "Is water wet?"
Unless they do for the precise reason of proving you wrong and then arguing against the point you are making.
This is the one time, "The exception that proves the rule," isn't sheer nonsense, precisely because it is.
Did OP wrote his own title ? Currently the article is titled "Windows 8 – Who moved my desktop?" which is an exception to Betteridge's Law.
"Windows 8 – Who moved my desktop?" was also the title when I saw the article six hours ago shortly after it was submitted to HN. My comment was regarding the title of the submission.