Owing to the lack of options, this is only useful for linting CSS written by the authors or anyone who happens to agree with their opinions on what constitutes good CSS.
Crockford may be an opinionated cantankerous old goat, but at least he gives you options to dial down some of the crazy he's baked into JSLint.
* He's also awesome, but anyone who's worked at Yahoo! or glanced at the JSLint Issues list or Pull Request queue can attest that he has strong opinions.