If you're building I new site, I highly suggest going with a css/div design as compared to html/tables/spacers design. It's twice as fast, and a complete site redesign can be done from a single file. (Of course, that's only if it's done right : ) This is only the beginning of the benefits, contact me if you'd like to discuss it further.
An excellent article on the subject:
Can you explain what you mean by a low markup to content ratio?
Using standards-oriented design makes it easier to have less markup than displayed content. With a table-and-spacer type design, this is not the case. You could have twice as much markup as you do text content, or three times as much or five times as much, depending on how complicated the markup is. With standards-oriented design, developers want to get that below one to one.