Yeah, I registered for the demo the very first day this topic was posted, and I still haven't gotten mine. Registered for the Jeanne D'arc demo too and never got that either.
Since this stuff presumably all ships out of California (and I live in MI) I wonder if this stuff tends to be proximity based? As in its easier for them to ship this stuff locally and they just go down their allotments that way.
That or they have some kind of weird data on the buying habits of PSU memebers and "detemine" who is most likely to be influenced by a demo. In that case, sending a demo might be more influencial towards people who don't buy a ton of games, as the more "hardcore" are likely to "buy or not buy" it regardless of getting a taste. In other words, if you know anything about video games you kind of know already if God of War is to your liking. More casual players might still have a chance to be swayed.