I remember buying the WoW Collector's edition. It came with a little Diablo pet. That thing was really cool and these days it is very rare. Sadly, on one of the many occasions I quit WoW I lost that account and with it the Diablo pet.
I doubt Pantheon will have this sort of thing. Which raises the issue, what if anything should it have?
EQ1, EQ2, SWG, SWTOR, GW, GW2 CoH, CoV, FFXI, WoW, CO, War,TSW and a slew of free trials and beta tests