Geez. Too much time looking into such a simple thing. I'm a big fan of using the keyboard instead of the mouse -- much faster for me. No one seems to have a good answer for a keyboard mapping of pasting into PowerPoint 2008 for the Mac. Word, people seem to have. As close as I could easily get is using System Preferences -> Keyboard, Keyboard Shortcuts, Application Shortcuts. And none of the Microsoft Applications even show up so one has to use "All Applications". Lame. Here's a screen shot.