It is covered in the SHOT Show Report:

http://www.equipped.org/shot_show_2010_gear.htm#ACR

You snooze, you lose. It is an extension of the existing Safelife system. Clearly, it will work better with the new PLBs that have more reserve capacity. Clearly it isn't as useful in this respect as a SPOT with replaceable batteries, but it also adds some nice options.

Time will tell if the market will buy into this.