i think you'll find that most high end sites are running a custom cms
This might have been true five years ago. I don't think it's true anymore.
Examiner, NASA, Whitehouse, Sony (Sony Music), The Louvre, Zynga, the Brightcove, Symantec, DivX, Paypal and Twitter developer community sites, the US FCC and Popular Science are all on Drupal.
Wallstreet Journal, New York Times, CNN, Forbes, Reuters, GM, Sony (playstation), Washington Post, New York Times are all on Wordpress
The Onion was on Drupal and is now built with Django, which is more of a CMF than CMS (and people often say the same about Drupal). The Department of Interior is on some CMS whose name I can't remember. And so on.
It doesn't mean that a CMS is the right tool for spacecadet, but increasingly custom tasks require custom apps and content management is not usually a custom task. Want to build a Twitter competitor? Hire some software engineers. Looking to put a newspaper, community, blog, etc online? At the very least leverage a framework. Want to build a simple five-page site and you can write HTML like a fiend using Notepad? Go for it! But at the same time, you might also look into things like Twitter Bootstrap, Grid 960 or something like that to jumpstart your development.
Why would DW CS6 mention CMS? That's a bit like saying MS Publisher is no good for doing spreadsheets. Dreamweaver is tool that is used for building websites. It is not a CMS.
No, it is not a CMS, but it has touted its improved integration for designers with the better Live View in CS5+
Some people in the Drupal community set it up to enable a live view and direct editing of template files