haunted? something is with you....Follow

OK I did the beta mostly working te DK and some of the warlock stuff at 80... never really paid attention to the effects. Now my warlock has the haunted icon on he buff bar and the the ghostly thing that follows me around, so whats the purpose? I cant seem to find any info on it and the one time I did post in beta I got no answer back. Anyone know what the purpose of the ghost that follows me around but doesnt contibute to any attacks? heheh

its kind of annoying...

ah the haunted momento... never really looked at it... hehehe thanks