Double-tipped Stylus: Make the stylus do something different if I flip it around. Erase, copy, etc. You could probably sense this with some kind of near-field RF sensor.
Finger friendly interface: If the stylus is docked, enlarge the icons, make it easy to do simple things like reading email, checking my calendar, etc, without having to pull out the stylus.
Tabbed browsing in IE Mobile: I hate that I don’t have “Open in new Window” on my Axim, but tabs would probably be better since task-switching is such a pain on Windows Mobile.
Autocomplete learning: Give me the option to automatically add any manually entered words/phrases into the autocomplete dictionary. (email addresses come to mind…)
WiFi Sync: I get the security thing, you guys did what you had to do. If you can’t get this back in as a patch in Windows Mobile 5.0 with ActiveSync 4.0, please get it back by the time Windows Mobile 6.0 comes out.
Podcasting in Windows Media Player Mobile: Both publish and subscribe. Integrate with MSN spaces if you must, but give me the option to autopost to custom blogs when I sync/connect.
Multiple Profiles: Let me set up multiple personalities and/or profiles on the device and keep them isolated. Families could share devices, work teams could too. This would lower the barrier to entry for the Windows Mobile platform, and eventually everyone will want their own device.
That’s all for now…