dl dt
{
width: 50%;
}

with TDs the rows will be aligned just fine. with DTs you have to fix one width and live with it for the entire site.

I don't think I understand what you mean when you call the use of "DL"s as being more "semantic" than tables.

I'm also confused as to what makes a table less sleek or more bulky. It seems to me that if you use "TH"s instead of a title class then Zack is right. Could you specify what makes the method cleaner or better?

I'm also confused as to what makes a table less sleek or more bulky. It seems to me that if you use instead of a title class then Zack is right. Could you specify what makes the method cleaner or better?

The most important factors for SEO that are under the author's control are the words in these places:

The Web page's URL
Links pointing to it from elsewhere on the same website
Its title tag
Its properly tagged headings
To a much lesser degree, its contents

Two other very important factors that are usually not under the author's control are the words in links pointing to the Web page from other websites and the perceived authority of those other websites.

But the markup of data tables and lists? You want to do it right for a lot of reasons, but SEO isn't one of them.