Shadow Priest AddOns?
 

I just saw this Weak Auras and I'm wondering if there realy is no addon around to track this:

Auspicious Spirits / Shadowy Apparition Tracker
A display to track the number of Shadowy Apparitions currently in flight towards targets. If a target dies, the Shadowy Apparitions will not grant Orbs when they 'hit', so they shoud be removed from the count

Just found this awesome AddOn:

http://www.curse.com/addons/wow/conspicuous-spirits

Ooooooohhhhhh! Great find!

Now also on wowinterface, the author has improved the AddOn a lot already!