Presentations coming to Google Docs & Spreadsheets.
Taking a snoop into the new (mentioned everywhere) Google Doc & Spreadsheets javascript, I found an the icon for Presentation. Presentation is basically Keynote on Mac or Powerpoint on Windows.
The Presentation icon 
might join the already implemented are the Google Document icon 
and Google Spreadsheet icon 
.
It seems Google is pushing towards the Office App that has been rumored.