Demaestro - 10:30 pm on Sep 9, 2010 (gmt 0)
Fireworks is great, but it's HTML, CSS and other rendered code is bloated, not SEO'ible, and sites that they create are hard to have to look good across many different browsers.
What happens when FW or DW automated code won't do what you want? Trust me it happens a lot with those tools because they can only do a "best guess" they can't produce good code without you going into the back-end and tweaking it.
If you have no knowledge of HTML, CSS, and JS then you will be pulling your hair out trying to get FW to do what you want.
It uses image slices for crying out loud. I know that may not mean anything to you but it is ugly personified.
If you are serious about creating, updating, and maintaining websites then you have to have at least a basic understanding of these things.