Southwest is a popular airline and has a popular mileage program that seems to be 100% revenue. Very few FTers seem to use it (I myself never fly Southwest, only because they don't service my airports well), but customers seem to appreciate it. Many people i know in California use their Southwest cards and fly Southwest religiously. So FF programs will exist in some form. They will just be more revenue based, particularly within the US. International redemptions will probably remain zone or mileage based in some form; they will just be devalued. The issue is that there are too many points out there, not the programs themselves.