And by this you mean … ?

Just read this in an RFP, what do you think it means?

"The site should be 99% accurate in IE7, Firefox 2 and 3, Safari for Mac and PC, and Chrome"

How do you go about measuring 99% accuracy of a web page.  Does this mean pixel perfect rendering to your designer’s PDF file, non-websafe fonts and all? My engineering brain can’t figure out how to discern 99% accuracy across 4 different browsers/rendering engines.  At least they were smart enough to leave out IE6.