If you enable the Develop menu in Safari, as covered in this hint, however, you can fix the problem. After enabling the menu, just select Develop » User Agent , and select one of the Firefox entries (2.0.x Mac, for instance), you will find that all features are enabled.
[robg adds: I'm not a huge user of Google's apps. I did, however, run a quick test with the Presentations module, and this trick certainly seemed to work. Before making the switch, I was warned that Safari wasn't fully supported, and that warning went away after changing the user agent. I also exchanged emails with the hint's author, and he states that he's not yet found an issue with a feature not working in Safari.]

