I agree that the rules strongly emphasize combat over roleplaying. Just look at all the "Is CHA your dump stat?" threads and see where the emphasis lies.
That said, I would mention that things like combat tend to
need more rules than things like social interaction. If you've created an NPC who's the Maciavellian ruler of the city, and the party has to get him to agree to a plan (or whatever), a few Diplomacy rolls and/or the players making their case in-character plus some imagination is all that's required. If the party fails to persuade and ends up cheesing the ruler off so badly he orders his guards to attack, then the exact flanking rules, etc. are going to become pretty important to you and your players pretty quick.
However, I
do feel that the sheer amount of combat-oriented rules, items, "Crunchy bits" etc. in the books tends to color peoples' perception of how the game is to be played. What disturbs me about it isn't so much all the combat-oriented stuff as the
lack of roleplaying guidelines. There's very little in the core books (or most of the supplements I've read) that really addresses roleplaying and character development. It seems to be sort of a "If you care about that stuff, stick it in wherever you want." attitude.
Anecdote from personal experience:
I started co-DMing a homebrew campaign setting a few months ago. We (the DMs) decided to adopt a "core books only" approach. In other words, no splat, no Faerun feats, etc. (we have been playing a Silver Marches campaign). I told the group that this would be core rules, but I would be using a few of the variants in the game. One of them was "Story-Based" XP awards as opposed to straight combat/CR awards. I wrote up a lovely little pdf and sent it to the players explaining how there characters needed
goals and that it was by judging the goals' difficulty and their progress towards the goal(s) that their XP would be based. I also suggested that we get everyone together and make characters as a group, that way the DM(s) would be available to answer questions, approve character story hooks, etc. Also, the powergamer-style players could help the RP-ers with some of the crunch and the RP-ers could offer story suggestions in return.
Long story short. The day came for folks to make their characters. One of the powergamers finishes up and says, "Are we gonna play today?" I tell him no (I had specified before that it would be generation-only that day because I didn't want folks to rush through the process

).
I ask the PG-er, "Let's hear your backstory and goals."
"Huh?" he replies
Me: "I need your goals or you won't be getting much in the way of XP. Remember the file I sent you last week?"
PG: "You mean that junk about stories? I skimmed it, but since we're using the core rules, I thought we weren't gonna do that."
Me: "The provisions for that kind of XP award is in the DMG, it's just a variant."
PG: (Aghast) "But that's not really IN the RULES, that's just -like- a theory!"
-sigh-
This has gotten longer than I intended, but I think that the right group can make what they want of the system as is, but there is definitely a tendency -as written- towards moving down a 10' corridor, checking for traps, killing the monster and looting the room.
YMMV, IMHO, blah blah blah
