Microsoft offers Internet Explorer 7 Public Beta 3: "New features and functionality in the Beta 3 release include:
All security updates for IE7 released through June.
The ability to drag-and-drop reorder browser tabs in the tabbed-browsing bar.
The reappearance of the optional read e-mail button for the customizable 'Command' bar, or main toolbar.
The Web page zoom-in scaling feature adds a horizontal scroll bar automatically.
A global RSS feed settings dialog.
A global RSS 'refresh now' function.
Additional work carried out since the Beta 2 release aimed at improving Web-site compatibility. "
Very impressed with IE7 beta 3 so far...