Actually, layers, or absolutely positioned divs, should be avoided whenever possible. They have their place, but often they end up being used where they shouldn't be, and then pages break when viewed with different font sizes. This is why VSD only works at 96dpi.
Cary, your post is unsubstantiated. Ever heard of the z-index? Absolutely positioned divs should be avoided? Take a look at this code..
<div style="padding:0;position:absolute;width:1px;height:1px;left:0px;top:0px;border:0px solid black;">
<p>my content</p>
</div>
</div>
Place that code above or below any element in a page and position it absolutely using the left and top values on the inner div and get pixel perfect precision in any browser. Tested, tried and true for about 10 years now. If abs divs have their place, where? You didn't say. You also didn't say where not to use them.
In regards to different font sizes, you can set the font size for a web page in a style sheet that's consistent in all browsers released in the past 5-7 years. Look up Eric Meyer's CSS reset.
I'm not sure how VSD and font size have anything to do with web page development. You're probably speaking about your system font size.
I'm not picking a fight here but it's posts like this that get my blood going.
G'kar,
I'd consider CSS strongly simply because you will spend double the amount of time styling a table than you would a div container. Think of it this way... if you feel you have more control over a layout using tables, try layering a table over another without using CSS. Cut out the middle-man (table) and go straight to the supplier (CSS).
Be well.