Adobe Dreamweaver CS4 Beta includes following new features ::
View your web pages under real-world browser conditions with the new Live View in Dreamweaver — while still retaining direct access to the code. The new rendering mode, which uses the open source rendering engine WebKit, displays your designs like a standards-based browser.
CSS best practices
The Property inspector’s new CSS tab shows the styles for the current selection as well as all the applicable CSS rules. Hover over any property to view a tool tip with jargon-free English explanations of CSS principles. New CSS rules can be created and applied in the Property inspector panel and stored in the same document or an external style sheet.
HTML data sets
With HTML data sets functionality, you can create your data in a standard HTML table, a series of div tags, or even an unordered list and then choose Insert > Spry > Spry Data Set to integrate that data into a dynamic table on the page with sortable columns, a master-detail layout, or other sophisticated displays.
Photoshop Smart Objects
Photoshop and Dreamweaver integration has evolved to the next level of compatibility and functionality. Drag and drop an Adobe Photoshop® PSD file into a Dreamweaver page to create an image Smart Object.
Dreamweaver integrates Subversion software for a more robust check-in/check-out experience with file versioning, rollback, and more. Once you’ve defined Subversion as your version control system, you can update your site to get the latest versions of its pages directly from within Dreamweaver; no third-party utility or command-line interface is required.
Adobe® AIR™ authoring support
New user interface
Work faster and smarter across Dreamweaver and other components of the next version of Adobe Creative Suite® thanks to a new level of integration and common user interface elements.
Read the release notes for additional details regarding the Dreamweaver beta.
– Naresh Khokhaneshiya