In the UK at least It's courteous to keep the landline for incoming calls. Many people - I do, too - have a 'free' tarriff for phone calls to landlines up to 59 minutes, but are charged for calls to mobiles. It depends on your caller profile, I guess; once the majority of people also have mobiles with unlimited minutes this isn't important, but t'ain't true of the folk who habitually call us, yet. This includes family...