Eyonix, one of the Customer Managers at Blizzard, mentioned on the paladin boards that Blizzard is looking at ways to improve Paladin tanking. One of their goals, however, is specifically NOT to give paladins a Taunt-like ability. So there are now many posts on the boards tossing out different ideas. Here's mine, reposted for fun:
Here's an idea for tanking (sort of) that I think is reasonably different from warrior tanking, but is still flavourful for paladins.
Every paladin at level 10 gets a passive ability called Guard.
If the paladin is in front of the enemy, [melee] attacks made against a party member have a 50% chance of hitting the paladin instead.
Basically, the paladin can't force the mob to attack her, but she can put herself between the mob and her ally. This keeps the other person alive longer, and hopefully gives the paladin enough to time to truely regain aggro. It requires positioning, and since the mob isn't attacking the paladin, she can't "walk" it away or similar.
Then in the Protection tree we can have:
Improved Guard (5 pts)
Requires 0 points in Protection
Improves the paladin's chance to Guard a party member by 5/10/15/20/25%.
Frustrate (1 pt)
Requires 20 points in Protection
If the paladin successfully Guards a party member, has a 25% chance of forcing the enemy to attack the paladin for 6s.
Basically, deep in the protection tree, the paladin gets a kind of taunt. It's not very good, but relies on using the Guard mechanic. Plus the flavor is very obvious: "Stupid paladin blocking my attacks. Die Paladin!"
Perfect Defender (1 pt)
Requires Frustrate, 30 points in Protection
100 mana, 10s duration, 2 min cooldown
Increases the paladin's chance to Guard a party member by 25%. In addition, the first time the paladin successfully Guards a party member, the enemy is forced to attack the paladin for 6s.
This gives you pretty close to a guaranteed Taunt. You still have to do it through the Guard mechanics, so it's not as good/versatile as a true Taunt.
As well, the Guard mechanic would give us an added dimension in PvP. It doesn't seem likely that we are going to get any damage anytime soon, but we could use Guard to protect mages and priests, as we are supposed to do.
One more thing I'd like to mention is that I feel it is important for mechanics to 'fit' the class as much as possible. Divine Intervention is a terrible, terrible mechanic. You can only cast it on another person, who must be a resser AND in a position where she won't draw aggro when the fight ends. Compare that to the Warlock soulstone, or Shaman self-res. And yet the flavour of Divine Intervention--the paladin sacrificing herself to save her companion--is so strong, that the spell somehow works.
Hopefully this idea fits the flavour and 'sense' of being a paladin.