WORN - Write Once Read Never - new trend in hard disk production?

Yesterday I participated Hitachi Storage training, which was about new AMS 2500 storage and its new active-active controller. A few white papers can be found below. I attach two additional links. One which has some interesting info about disk failures (from FAST’07: 5th USENIX Conference on File and Storage Technologies) and one about risk of raid5 in disks bigger than 750GB. So - remeber the WORN rule - which make SATA drives compleatly untrusted