See I really really really don't think so.
You can't ignore some of the facts about the iPhone that make this highly unlikely..that we'll see a 3G and GPS phone anytime soon.
#1. The phone as WiFi. Depending on who you are and where you spend most of your time, WiFi can be something thats readily available, almost always. You will spend A LOT of time on WiFi with your iPhone. EDGE will fill in nicely when not on wifi, such as out on the road. Its really not that slow, its just not as fast as 3G. Plus, I personally would rather have full coverage just about everywhere (EDGE) than be part of a service that is strong in some places and weak or non-existent in others (3 G).
#2. GPS. Clearly not needed. Google Maps with integrated functions for directions, turn by turn, with Traffic. You don't need GPS. If you don't know where you are to begin with... you're an idiot.
All I am saying is that they will add new features with subsequent releases. 3G will happen, but GPS is something I was suggesting. None of us knows what Apple has in mind, but you can bet they already have ideas for the next version and the next, and so on.....