Non-combat story elements in D&D

This thread originated as an email conversation between a limited set of people, but I think it's a great topic for general discussion, so I'm distilling it here. If any of the earlier participants want to elaborate on their points or contest my distillation as out of context, please do so.

The question is, does DnD - specifically the latest edition as of this writing, 4th Edition (4E) - support stories with dimensions other than combat? Or is it simply a skirmish game with associated story colour, or "cutscenes" if you will, intended to tie the encounters together into a coherent whole?

Here are a few of the opinions and findings that people made in that email thread:

• DnD supplements contain a wealth of setting material riddled with plot hooks for playing scenarios with different foci than balanced combat encounters - espionage, diplomatic missions, social power plays, etcetera. Are these supplements worthless or misleading given that DnD's rule set is primarily about skirmish combats?
• DnD 4E has more rules - or at least "system bits" - for non-combat activities than many previous editions do, and thus may be more suitable for such play than earlier versions were. Social skills (Bluff, Diplomacy, Insight, Intimidate), utility powers, rituals, skill challenges, quests, etc.
• The emphasis on battle maps and positional tactics has led to DnD 4E being a very well-developed skirmish game, superior to earlier editions. This may lead people to feel that this is "all the game is", ignoring the bits that aren't as well-developed.
• Many other games (WFRP3 was the dominant topic of discussion) appear to have more defined systems for social conflicts, but this may in fact be a ruse - in the end, it comes down to the use and interpretation of social skill rolls anyway, and DnD's skill challenges map pretty directly onto WFRP3's progress tracks used for more important social conflicts.
• WFRP3 has a few features making it more suitable for social conflicts, such as richer rolling (i.e. less binary outcomes) and specifically social classes / actions.

And what I think is the main topic of discussion and intriguing contention:

• Prior to the wealth of new-form games, which often puts social conflicts front-and-centre or treats them the same as physical conflicts (read: Dogs in the Vineyard, Primetime Adventures, Burning Empires, Fate, Technoir, to name just a very a few off the top of my head), nearly all games lacked systems for social conflicts, but that didn't stop those who wanted more non-combat play from integrating it. By some assertions, this led to even richer play, as there were few rules other than some GM-interpreted skill rolls to keep the reigns on what happened; social exchanges came more fluidly and naturally to most, than if there were dice rolls and mechanics involved.
• DnD 4th Edition, with its lack of hard rules surrounding the use of social skills, capture this old-school feel. It's not that social conflicts can't happen, it's that when they do, it's not intended to be systematized but rather worked out in-character and organically between the players, as moderated by the DM and the occasional use of a social skill roll to shape the narration and resolve impasses.

Call for comments:

• Do you feel it's true that DnD 4E (and maybe earlier editions of D&D as well) is good for nothing but dungeon crawling and tactical combat?
• Do you feel it's true that social conflict systems (and indeed, any conflict system other than combat resolution systems) add to the non-combat dimensions of an RPG, or are they distractions or even active hindrances for such play?