DaveW,
When the software for the 1197 (and other units that already have the Ethernet port) is released; it should have the same Ethernet capabilities as the 1198.
Harry,
The advantage of an Ethernet port is in the amount of data that can be sent back and forth over it. Humminbird may allow additional accessories to be connected to your Humminbird unit (or the other way around) but nothing official has been stated yet. To begin with they have stated: Waypoints, GPS data and Sonar. So far though the specifics on what sonar data can be sent from one unit to another has not been defined. I imagine that once the Ethernet communications are turned on that we will start seeing regular software updates that added more functionality for the Ethernet function.