Newton cometh...wifi and bluetooth for web access with your 3G in your pocket. My speculation anyway...
I really wish people would stop speculating on a new Newton... the iPhone and the iPod Touch IS the Newton replacement. About the same size and form factor but way more advanced and everything you just mentioned (WiFi, Bluetooth, etc.) is already there.
If Apple does release another touch based device, it will either be a Tablet (12 or 13 inch multitouch screen possibly called the Macbook Touch) or a smaller cheaper iPhone nano, but a Newton is already what the iPhone is. In other words, to be clear, the iPhone is the evolutionary descendant of the Newton. How much different could a new Newton be than what the iPhone already is?