Viewing Powerpoints on the iPad is a crapshoot. I have yet to see one not get butchered in the translation. Either the bullets are off, the fonts, and forget graphics. I have Goodreader and Quickoffice Pro. I am guessing it's the squabble between Microsoft and Apple, and Apple not feeling compelled to support anything Microsoft. Plenty of examples of this nonsense, with us users stuck in the middle. 🙁
The only way I have been able to view complete and accurate Powerpoint presentations on my iPad is converting them to pdf.