Tables are and always will be a good design tool for users and SEO,, dont fall into the “We must all use strict CSS” its really not the case as all.
if you like for formatting your site, use the CSS, as you dont display data that really requires a table. Tables are mainly used for data that should be in rows/ colums not a complete layout but table work with all browsers, somthing CSS cant really say 100% yet!
hope thats not more confusing than you wanted but in short.
CSS – used for layouts, can go to hell in a different browser, clean code
Tables – Used mainly for displaying data, can be used for layouts but heavy code, works in all browers.