I am on the 3G-HSDPA-1G bundle, for which I am charged R599 per month. But on Vodacom's website the cost is shown as R499 per month. So which is correct?
R499 is the price of the ad-hoc bundle charge only. Seeing as you took out a contract it was probably for the card. You are paying R100 a month extra for the card which is exactly how a 'cellphone' contract works.