1. Div Loads faster than Tables
2. Tables can be inflexible
3. Accessibility issues are easier with DIV
4. Tables don’t print as well
5. Div is great for SEO – powerful to do content positioning. So basically you can place the bulk of your rich content closer to the top of your HTML code, but it will still render on the browser in the same place
6. DIVs can reduce the size of page - Use of DIVs and CSS can allow you to reduce the size of your HTML significantly, depending on how nested your tables are. TABLE tags require, TR, TD, and some cases include, TH, THEAD, TBODY, TFOOT. This adds quite a few tags that can all be condensed into a few DIVs.

There are a number of reasons why CSS is superior than tables for SEO:

Smaller file size makes it easier for Search Engine Spiders to crawl through your website.

Less junk markup makes it easier for Search Engine Spiders to decipher between code and content. Ideally, try to keep your content-to-code ratio as high as possible (more content than code, obviously).

Structural organization is greatly improved by using h1, h2, h3 tags ensuring that the Search Engine Spiders know what you’re trying to show them. Font tags cannot communicate a page title or header, even if the font size is larger. Either way, don’t forget to include important keywords relevant to your target audience (i.e. If you’re selling motorboats in a small town in California, use “Motorboats in Small Town, California” rather than “Motorboats”). In addition, if you’d like your h1 information to appear after your body tag (or near the top of the page’s code) but don’t necessary want the h1 information to be visually displayed at the top of the page, then CSS will allow you to using absolute positioning which gives the designer freedom to place the h1 information practically anywhere on the web page

No more Javascript rollover effects. CSS allows the designer to program a variety of rollover effects (images, text decorations, etc) that are defined within the CSS style sheet. This method allows the Search Engine Spiders to focus more on your website’s content rather than unnecessary Javascript markup. If you’re looking for fancy, Flash-like rollover effects that combine CSS and Javascript resulting in graceful, lightweight rollover animations, then take a look at the latest that jQuery or mootools has to offer (thats for another article).