While I don't expect the Leader to have any ability of compulsion over fellow party members, I do think there will be groups in which the Cleric or the Warlord will be assumed to lead solely because it is described as his party role. That isn't specially aggravating, but it can be annoying at times (having played in groups whose DM always required someone to be elected the "party leader" and often seeing such things being determined not based on ability or inclination but rather artificial expectations as "the Fighter, of course, he is the strongest" or "the character with the highest charisma, obviously").
In my experience, many players that end up in the leader role take on more active classes like Fighter or Wizard. But that may be due to the significant lack of clerics in most of the groups I have played. 3.xe Bards where character "who place others (through suggestions, commands, pleading, what have you) in situations where they can use their strengths and who inspire others when the chips are down" and I never saw a Bard as a party leader in a D&D game.
I still think that "Cleric" should be reserved for a character whose primary role would be to conduct masses, offer spiritual advice, serve as an ethic compass and lead congregations. Much of that isn't what a member of a party group will be doing and if so, he's abilities are wasted on such a small group of disparate individuals rather than in a community. From my perspective, most D&D "Clerics" are rather just another form of Holy Warrior - wearing armor and wielding a weapon while blasting enemies in a battlefield.
@WotC_Miko:
Hey, that's great. I guess designers couldn't think of a better name for Leaders than. Otherwise, I can't see a reason to take a name that naturally leads one to associate the role with "Boss" and then have to write a sidebar saying it is a Leader, but not a Boss.
Thanks for the insider info anyway, WotC_Miko.
