To view HD trailers in Flash (JW Player), just left click on the resolution you want. Most trailers will work in Flash, but we've defaulted all Apple trailers to use QuickTime to work around certain issues.
To view HD trailers in your preferred browser video player (most computers default to QuickTime), just open it in a new tab or window. To open it in a new tab, middle-click the resolution you want OR right-click the resolution and click on "Open in New Tab". To open it in a new window, right click on the resolution you want and click on "Open in New Window".
To save HD trailers to your computer, right click on the resolution you want and click on "Save Target As...".
Apple has blocked direct downloads via the browser, but there are workarounds you can perform.
If you downloaded a Yahoo! trailer and got a file with a DLL extension, just rename the extension to MOV and it should just work.