I use them both for example
<table class="table1" cellspacing="0">
where the table1 is
{
border: 0px;
padding: 0px;
width: 95%;
background: #f3f3f3;
color: #000;
}
I recommend using both unless you are a pro in css. Since you could really screw up a layout with 100% css in a crossbrowser enviroment.
SE's do like less tables and it is far easier to manipulate. But I think the above combination woks the best for me. Safe, controllable, same amount of code as div tags 100% css.
CSS has had my attention lately. A friend and I have been playing with new versions of my HP in all CSS. Even the NavBar, all of it. We have tested it in Firefox, Netscape and IE and only really had minor issues in Firefox. The rest went just fine.
CSS is the future of my websites. As stated above, cleaner, lighter and easier for me to read as well as for the spiders because there is less of it.