[mjac]

That's a great point. Photoshop has extensive capabilities for visual rearrangement and transformation. Once the core design is created it can be cut up and extended with further XHTML/CSS elements (minimally for consistency).

Quora does not compare with even basic designs found in CSS galleries (http://cssbeauty.com/). Most are graphic heavy and use intelligent slicing for fast, aesthetic experiences.

For rapid design, you can use the 960 grid system (http://960.gs/) to speed up mockups, then implement the layout on top of 960's positional CSS. I tried this for the first time with my new design (http://mjac.co.uk/) and I think it produced a significant improvement in aesthetics and organisation over my previous XHTML/CSS mockups and completely custom Photoshop layouts.