Paper tank nto only refers to those DD tanks that can't take a hit it also refers to those clueless morons who can't hold multiple agros.
My choices?
First is Warrior, because MOST(not all) people who play this class know they are a meat shield.
Second is Paladin, maybe I just haven't met enough of these.
Third is Ranger/Bard, if they are built to tank.
Dead last is Shadow Knight, this is where 90% of the snobish paper tanks come from. Just because they can solo mort yellows and a few reds they think that with a group behind them they can just whip everything in sight worry free, and that's just how they are too, worry free. They don't worry if they taunt/bait or whatever their skill is called, hell I bet they can't tell you what the skill is called. If I am ever forced to group with one I will send a tell to the healer to watch me and rip agro from the SKs inept hands every time. Yes there are some that I have seen do a good job and I have some friends that play them and I HOPE they do a good job. I'm not disrespecting their ability to DD/manage agro, it's just that this is a very good solo class so I have a feeling these guys grow too fast without gaining good group experience. If I offended you then GOOD that probably means what I have said applies to YOU.