Brazilian website MacMagazine links [Google translation] to YouTube user LeopardOctober, who has been posting video previews of new Mac OS X 10.6 Snow Leopard features. Many of the features have already been described, but the videos provide examples of the features in use.
In HD + NEW - Snow Leopard Build 10A261: Demonstrates "Put Back" feature that restores trashed files to their original locations, Finder window slider for resizing icons, Stacks "drill down" navigation, the ability to play videos directly within their Finder icons, automatic date and time stamping of screenshots in the file name, organization of the Services menu by type, and a new preference pane within Keyboard & Mouse offering expanded keyboard shortcut configuration. Several of these features were described several months ago.
Dock and Substitutions - Snow Leopard Build 10A261: Illustrates the ability to easily assign applications to specific Spaces directly from their Dock icons, and "Substitutions", which offer several auto-correct/auto-format features and expansion of the Data Detectors feature that automatically finds text such as dates and times and automatically provides links to operations in related applications such as iCal.
Finder Preferences - Snow Leopard build 10A286: Shows Finder preference allowing default searches to cover the entire Mac, the currently open folder, or whatever the previous search scope was.
QuickTime 10 - Snow Leopard build 10A286: Runs through the menus present in the new QuickTime Player and illustrates the "Trim" feature and Save/Export options. Details on the new QuickTime have been trickling out for the past several months.
Article Link: Snow Leopard Videos Demonstrating Several New Features Surface