The problem with Bitcoin is that nobody has found and it may well be impossible to find a way to develop a fee market, in the, absence of a block subsidy, that does not over time converge to one of two undesirable results: Fixed blocksize and infinite fees or infinite blocksize and zero fees. Mike Hearn has made a very persuasive argument as to why a fixed blocksize and infinite fees is such an undesirable outcome; however I am sure that Gregory Maxwell can make an equally persuasive argument as to why an infinite blocksize and zero fees is an equally undesirable outcome.