No mention of different prices for 32-bit and 64-bit versions. Seems that both will be provided in the boxed set, but you only get the Product Key for the one you pay for.
Makes sense.
Interesting to see what the Australian prices will be. At 80 cents US to $1 AUD, the Full Ultimate price of $US 319, gives $AUD 398 – a very convenient (large) number.