It would seem to go without saying that a winning CV should have correct spelling and grammar, and be visually appealing. Yet of the hundreds of CVs that come past my desk every year, I see very few that meet even these basic criteria.
You need to put yourself in the employer's seat for a moment: you're about to invest tens or even hundreds of thousands of dollars into a stranger, in the hope that they will prove not only to be worth the investment but will enhance your business. If this stranger cannot even be bothered to present their details in a clear, concise, and accurate manner, what does that tell you about their attitude and capabilities?
As a CV writing business, we are seeing more and more that people with CVs that at first glance would seem to be quite well set out and have strong histories, are not getting interviews. Employers are becoming more discerning and cautious, and are looking for more "proof" of a candidate's potential.
The two factors that we find are achieving the best results in the current employment climate, are to present employers with an aesthetically perfect document that provides them everything they are looking for quickly and easily (it doesn't need a flashy format) AND shows the employer what the candidate has achieved for other employers. This is what turns a CV into a powerful marketing tool.
Again, put yourself into the shoes of an employer: you've received 50 applications - some are 6 pages long (you don't have the time!) - some have incorrect spelling and grammar (I'm not going to let that person prepare my important business documentation!) - some are full of big claims (where's the proof?) - and then there's one that clearly provides the information you are looking for with facts and figures to demonstrate what you have achieved and when (let's get this person in for interview straight away).
It's as simple as that :).