From GM Shakahn:
Ever try to stalk the beggar, or a pesky goblin, and have them leave you in the dust as they move away, leaving you with that lonely feeling? Well, lets just say, that when you stalk them, you are STALKING them.
You can now stalk critters and NPC's and follow them around when they move. This is not quiet the same as stalking a PC in which you move with them instatanious. There will be slight delays as you move about with the NPC/critter. If you want to stop, just stop stalk and/or unhide, and when the move again, you will not follow.
UPDATE: Stalking has been updated, a bug that allowed those who were being stalked to see "You have lost your Mark" has been taken care of, so no more should they see that message, alerting them someone is trying to stalk them.
With either of these, if you find a bug in it, please place a note on the BUGS board here. Thanks.
GM Shakahn