I think it would be important to ensure that when testing a new version they only had to pay once through the beta version process i.e. pay for beta 1, have betas 2 through 6 and the final version at no additional cost. There might be some reduction but it would be interesting to see how reduced that might be. Besides, following the talk of 4 or 5 betas, I don't know how anyone could resist! I for one, as a rather non technical user, ususally try to hold out til the final version but in the hype and excitement can never resist downloading early, particularly when I rationalise the fact that I probably spend not far off that money for lunch every day.