Well, difficulty is a real number, its not a referance number
I fully agree that we need a more "human interpretable" form of a difficulty stat, Telling someone that the difficulty is 7,673,000 and that its going to rise up around by 1-2million more Really doesnt mean much to them, its just confusing to hear that "a bitcoin is now 7673000x harder to get than it was when it was first released" it really doesnt tell us much.
Right thats approximately meaningless. Now the original or minimal difficulty is 2^32 so 7,673,000 x 2^32 is approx 2^55. How easy is that in comparison because 7,673,000 ~ 2^23. (I guess I must've mistranslated it before 55 not 52 bits)
And when you see a bitcoin in hex (like with hashcash because that is what the coin is) you can visually *see* those 55 bits. This is the latest hash from the block explorer:
http://blockexplorer.com/block/00000000000000e3d3268e05a9901759c1452590d0838a80aeb8abaea59f1e9fand bingo I can count 0s (14 of them) multiply by 4 (bits per hex nibble) and I know that is a 56bit hashcash collision. (You get lucky and an extra 1 bit half the time, 2 bits 1/2 time etc).
Adam