So, I was just watching the Bungie Commentary on Building the Destiny E3 Reveal and noticed that the Duke Mk. 44 Handcannon was in the special slot (along with a fusion rifle and shotgun). Anyway, I thought that was interesting that at one point Bungie considered treating hand cannons as specials.

Edit: They're certainly special to me. ;)

I think one of the last bungie podcasts talked about this change. Been a while, though...