Time required to implement a simple code snippet using standards-compliant, CSS-based XHTML: five minutes. Time required to include all the box-model hacks, shims, whitespace twiddles and so forth to make up for the fact that the simple code snippet renders five different ways in five different browser: an hour and a half for four out of five; no success for (you’ll never guess) Windows IE. Time required to start over and re-implement the layout using a bad old table: five minutes. Number of browser-specific hacks required: none. Amount of code required: about half that of the CSS method.
I’m a big fan of XHTML and web standards — but its big benefits are supposed to be cleaner code and easier development and maintenance. In a lot of cases we’re just not there yet.