I read your first post questioning Apple's ability to bring a better phone to market. I didn't respond because I didn't think you were REALLY looking for an answer. I believe you are firmly planted in your opinions and won't be swayed one way or another. It doesn't take to much of an imagination to project the kind of capabilities that Apple would include in a phone of their own.
Let me act as the readers imagination here.
An e-mail system: an e-mail system that is better than the Treo's or even a Blackberry by giving you access to your "desktop" account (or any other account that you may have) while keeping you in perfect sync with it.
Carry this idea through with iCal events. Once Leopard comes along in the next couple of months, we will see the introduction of iCal servers. This will let you edit your iCal events where ever you are and keep them in sync across many computers. So say Apple releases a phone; it could have the ability to automatically have access to this data in a live manner. No syncing required. It is always just there and is always current ? maybe you have it accessing your Mac at home to get this information, or maybe your Mac at work (a desktop machine or a work server) or maybe even just simply having a .Mac account in which Apple's servers would provide this always available syncing capability.
Contacts? Instantly available everywhere as well. Say you get a slew of new contact numbers at a business meeting... at Joe's Pub...
they are instantly available on the desktop.
No docking of the phone at the office needed. It is just available. You may even get to choose in which manner they are instantly available. Maybe via wi-fi, maybe via Apple's .Mac services... maybe via... something else, like maybe a new T-Mobile partnership (purely far-fetched speculation but certainly possible as far as I know; keep in mind all of this is just projecting based on what Apple is capable of and based on their usual business tactics).
These ideas will of course carry through with iTunes. And it seems obvious as well that iTunes songs will take on new functionality in various ways. Like providing users with new ringtones and allowing them to use these very same songs that are on the phone as "Please Hold" music. This will all be done with ease utilizing Apple's incredible UI. An Apple phone could probably even have access to the iTunes Store.
I do not think it would be very far-fetched to expect an Apple phone to be able to interface with an iPod either. The phone would of course be able to communicate with a Mac and it would probably be able to communicate with the .Mac services so it would also stand to reason that it could communicate with other Apple products such as the iPod.
This would be done to give users more capabilities and flexibility but also to secure a Halo type effect in which you would be more inclined to purchase additional Apple products.
Maybe you are on the road or at work and you want different music on you phone. Just plug it in to an iPod and get what you want (this would certainly be possible now that Apple has no restrictions on uploading music from the iPod, as long as its registered).
To continue projecting capabilities, it would certainly be feasible to see widget like capabilities on a phone from Apple. After all, Nokia's series 60 phones have been using this underlying Apple browser and javascript technology on their devices for at least a year and a half now. About as long as Motorola has been using iTunes capabilities on their phones.
Apple has been using these companies as a test bed and learning everything they can to incorporate into their phone - should they release such a device.
It would also seam feasible that Apple could incorporate a motion detection system into the phone to possible use as an interface element. They have been using this kind of technology in other products like Mac Books and iPods and the Nike/iPod device to do things like sensing sudden acceleration and then instantly parking the HD to protect it. Maybe they could use these same sensors to detect other types of motions (maybe multiple opposing motions for example), like sensing if the phone is squeezed in order to quickly turn off that embarrassing ring in the middle of a theatrical production without fumbling for your pockets in the dark and trying to find a switch.
Well, these are just some of my ideas. I have many more but not the time.