Google redesigned Presently and added the old-fashioned menu already included in the word processor. The interface have been streamlined and there's more room for editing slides.
A notable new feature that can be found in the Slide menu is zooming in/out, but the keyboard shortcuts aren't very intuitive: Ctrl+Shift+left/right arrow.
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Google Presently today
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Google Presently at launch (September 2007)