Charisma: The Ultimate Ability

[Haphazzard]

I really think the only thing wrong with the charisma in 3.x is the flat dc.  I saw a chart made out for calculating dc's based on the relationship of the two characters, what they're trying to accomplish (leave 5 minutes early v.s. assassinate your king), and even the underlying motives of the character being persuaded.  The beggar in your example would get a +0 for relationship because they're strangers, but after a few fails the cleric is annoyed and they are in poor standing.  This would give him a negative (maybe 2 or 3).

As for all the synergies and getting a +30 at lvl 4, think of what that character  isn't getting in...everything else.  If his stats are pumped into talking, what are his chances of making it up that 50 foot rope out of the flooding cave (can't pursuade water).  If you're pumped into talking your chances of surviving to lvl 4 from lvl 1 are probably pretty low unless you do a lot of standing in the back throwing rocks and hoping not to get hit.  So, it DOES have it's drawbacks.

[Bill Volk]

Charisma is far from useless, but it's not the uber-stat you make it out to be.

The reason? Only one character in the party really needs it. A party benefits from having two characters with high Strength or even Intelligence much more than it benefits from two characters with high Charisma. If a party has two or more "talky" characters in it, like a bard and a sorcerer, or a paladin and a talky rogue, they're probably going to step on each other's toes and fight over everything.

So, Charisma can still be a dump stat about three-fourths of the time.

[SDragon]

As for all the synergies and getting a +30 at lvl 4, think of what that character  isn't getting in...everything else.  If his stats are pumped into talking, what are his chances of making it up that 50 foot rope out of the flooding cave (can't pursuade water).  If you're pumped into talking your chances of surviving to lvl 4 from lvl 1 are probably pretty low unless you do a lot of standing in the back throwing rocks and hoping not to get hit.  So, it DOES have it's drawbacks.

Depending on your class (IE: Rogue) and your INT bonus, you still have a pretty good chance getting out of that if you still max out Use Rope, Climb, or Swim. Also keep in mind, if you're only getting the other skills for the synergy bonus, you can ditch them after second level, using the skill points for other skills.

As for the "throwing rocks" scenario, the only way that I see Diplomacy getting in the way of combat is through the Negotiator feat, and lessening a single physical ability a bit. Just because you're "talky" doesn't mean you're physically incapable of swinging a sword around.