Here mostly pdf is used for slides, many are in LaTeX and contain complex mathematical formulas. As such PowerPoint is not practical. The PDF reader on the N95 simple does to cope at all with non-standards fonts.
I mostly use SymSMB to access public shares. A bluetooth keyboard to make notes (call it a hardware application).
Still for R&R Mobipocket is a major application. I am a fervent reader.
I want it to be a pocketsized computer with mobile sized touchscreen and mini-qwerty keyboard. It should have HDMI/VGA out and when connected the higher possible screen resolution should be supported so decent office work and desktop stuff can be done. A higher cpu-power mode for when hooked to a powersupply could be a blast to. 3x optical zoom. WiMax.