I'm about to buy order Snow Leopard, and I'm contemplating adding iWork 09 or MS Office for mac to the order. This year for school, I'll have to do several Powerpoint presentations for school. I'm entering a point in the program where I'll be rotating to different sites, having to give presentations. I've done a few simple ones in the past, using Google Docs or the PC's at school. I'm curious, as to whether Keynote will play nice with the PC's at school and other rotation sites. I only have enough $$ to buy one or the other, so I'd like to get something that's nicely compatible with Microsoft office for PC.