the cellphone as technology integration platform

I carry way too many devices around

It makes sense to me that many of them could integrate together on the cellphone, specifically:
- cellphone :) that works anywhere in the world
- camera (at least 3 megapixels, turn the phone sideways so that it works like a regular camera)
- GPS (including ability to record tracks and download them to computer, as well as share the GPS to other devices using Bluetooth)
- MP3 player
- Bluetooth (and ideally USB) connections for additional external devices

If you want to go a bit beyond that, also nice would be
- WiFi and voice over ip (VoIP)

I don't think you can make your cellphone also a PDA, really a PDA should have a large screen and ideally a slide-out keyboard.  Cellphone should be able the size of a small camera - I don't know if it's practical to also have a large screen, although to be sure some small cameras do use most of their back space for a screen.

There are of course already cellphones that have GPS, but they don't make it externally accessible and I don't think they record tracks.  There are some with MP3.  And there are some with the turn-sideways 3 megapixel camera.

AFAIK the Sony Cybershot K790 is currently the closest to this spec.

The Nokia N95, with its 5 megapixel camera and strong GPS features, should also be a good contender, but it's not available yet - so far there's just CES coverage and such.

A good opportunity for Apple... and in fact there are rumours that the iPhone will include a camera, GPS, and iPod capabilties, and that they may even put GPS chips in their laptops (which would introduce the usual "easier to recover when stolen / but a potential loss of privacy" set of issues).