The only difference between the Android and CE units is the Operating System on the navigation side of the unit. The Android unit uses GPS to navigate, but as standard uses Google Maps which requires an internet connection to download mapping on the fly. If you install an offline navigation package, you don't need the internet connection all the time.
You cannot, IIRC, use the Market without an internet connection. You can connect a USB device to the Android side - thats how it gets its wireless connectivity.