Wen all is said and done, Dreamweaver is an expensive option unless you're building sites for a living. (We may acknowledge the existence of warez in these parts, but we don't encourage their use or distribution.) At $400 (full; upgrades usually run around half-price) it's a big bite out of the wallet, even if you aren't springing for the whole Creative Suite.
That being said, DW is an excellent professional tool. And it's an execrable n00b tool. The problem with DW -- a problem that it shares with all WYSIWYG editors -- is that it can insulate the developer/designer from the underlying code (HTML/XHTML) completely if you let it. Why is that bad? Well, contrary to what a lot of people think, it's not enough that your web pages look good and are functional -- they also need to mean what they say. That is, your headings need to be headings (and not just words in a different font, size, weight or colour), your emphasized text needs to have emphasis or strong emphasis, not just be words in italics or bold, etc. As long as you are aware of the structure of the page, you can do it right in something like DW. If you don't have a clue, you can build something that looks like a good web page, but that some people (mostly the disabled) and all machines (like search engines) are going to have trouble reading.
Frankly, I don't find Dreamweaver to be much help in my work -- but then I've been working with HTML since before it had a version number (and SGML before that), so I've had a long, slow, gradual introduction to the ever-increasing feature set over a period of time longer than a lot of young web devs have lived. And because I'm disabled, I'm a little more sensitive to accessibility issues than most developers are, so I pay a lot more attention to those niggling little details in the raw code (proper tagging, attributes that help with screen reading and keyboard navigation, etc.). I can work with any decent text editor, but since there's usually some server-side code (and because I'm fundamentally lazy and appreciate things like code completion and automatic tag closing) I find a good IDE (integrated development environment) worth its weight in gold. DW's code view is good in this regard, but (again) it's $400, while things like NetBeans, EclipsePHP and Aptana Studio are $0. I might have forgotten to mention that I'm, well... frugal would be one way of saying it.
So... Dreamweaver good -- especially if you plan on doing web design professionally. The latest version (or, at most, one back) will let you jump into any studio's workflow quickly if you're looking to work in the industry. If you're doing it on your own, though, and are not making money at it OR if you're developing sites that have significant dynamic content, then there are a lot of practical and economical alternatives that are only marginally harder to use initially (HTML isn't really that hard to wrap your head around) and likely to result in tighter code that is more accessible, more usable, and better for organic SEO.
