I continue to have a land line, for two reasons:
1) The rates for calling Germany are cheaper than what I can get for my mobile line. Obviously that's not an issue for you.
2) Landline infrastructure tends to be more robust than cell phone networks in emergencies such as floods, storms, continental power outages, and the like. I value the warm, fuzzy, secure feeling that this robustness gives me.
I'm not giving up my land line any time soon.