Thanks for the test Tom. That's not surprising to me.
The thing is with 64-bit software is while the processor fetches and works with 64-bit numbers, the applications usually just waste the extra space.
For example, if you declare a variable in a program to store an integer, it now takes 64 bits to store what used to take 32. Both take the same number of processor cycles to work with the number. What 64-bit allows is storage of a much larger integer (which for most things isn't needed) and for larger addressing (which is the most important 64-bit feature).
For the reason mentioned above, 64-bit applications will use more memory.
Basically, when you need 64-bit, you need it. When you don't it isn't that important.