I frequently use Google Docs for presentations I prepare for conferences. I do miss some of the features of PowerPoint and I do go crazy with some of the current quirks (font size craziness, bullets on bullets that won't reformat well, line spacing gone wild) but in the end it is still a better platform for the one reason this highlights -- the collaboration capabilities. It is so much easier for me to share drafts and get direct edits from people than it is emailing something back and forth and then trying to merge changes. It reminds me of applying patches to source code via email + uuencode + diff versus DVCS.