Language Nanny

I was getting a kick out of Kevin Drum defending his erroneous use of the phrase 'begging the question' to mean 'raising the question' rather than 'ducking the question'. Then I went over to Eschaton and found Atrios quoting a press release wherein some nimbnut thinks 'equivocates' means 'equates'!

Is NOTHING sacred?

If people have to change the meaning of words and phrases, do they have to change them to mean the exact opposite of what they started out meaning?