Amidst they hype many people have overlooked the OTHER data addon plans that Vodafone has released with the iPhone. On the pricing page there are also two Broadband for mobile plans that are now the SAME as on Vodem/VMC, as long as you take a 24month Term.
200MB $29.95 + 200MB topup for $10 more when you reach your limit
1GB $49.95 + 1GB topup for $10 more when you reach your limit
And you can put these on ANY voice plan.