Nixon or Vixen: Linguistic Deracination

Maybe it's American slang which causes this linguistic deracination. Wonkette was denounced as a "vixen" according to an article she posted to her website. I thought I knew what that meant, but I looked it up:

Main Entry: vix·en Pronunciation: 'vik-s&nFunction: nounEtymology: (assumed) Middle English (southern dialect) vixen, alteration of Middle English fixen, from Old English fyxe, feminine of fox

1 : a shrewish ill-tempered woman
2 : a female fox

So, basically vixen applied to a woman used to be pejorative. But, given that "fox" is now basically a good thing for a female person to be, or at least foxy, vixen is now ambiguous about whether it's a compliment or a rank.