Social skills are best handled with mature, cooperative players who will take the game stats of the other player into consideration when interacting with him. The trouble with social skills is that while they are great for simple tests (get past a guard, tell a lie convincingly, etc.), they disrupt roleplaying when interjected into PC interactions. Instead of having an interaction between two characters, the dice are being whipped out, and one of the characters is being told what his character does. And unfortunately, you have the choice of the existing highly subjective rules, with lots of potential arguments about modifiers and thresholds, or house ruling something that will probably be cumbersome and eat up even more game time at the expense of roleplaying.
Well said on all accounts, though I did want to elaborate on one specific account.
I was in a long-running(year long) shadowrun game that ran weekly, but our players did a LOT of party social when we could. The team was fairly well bonded, and would go out for drinks, parties, and occasionally talk and lie about the things they've done in the past. Lying, especially, as most runners aren't keen to give out details that can get their friends, family, or past associates hurt to near strangers. As we found out when our doctor's Judas quality kicked in. Ahem.
The interesting part was how we did it. I'm specifically thinking of the interactions between the hacker and the face. The face was a ridiculously high kinesics adept, who rolled a decent brick of dice for most things. The hacker(me) was only slightly less competent - he was made to include social engineering under hacking, and came with a decent charisma, the group, and some empathy ware - and we actually did use dice against each other fairly frequently. But not in the way you thing.
Both me and the adept's player were socially adept people who actually COULD put stats-to-play without dice, derive meaning and emotion from stances and positionings, or even the way people said hello. And more importantly, work information into our posts for the other to use. I think that playing-by-post, and not table, helps immensely in this regard, in that its much easier to make longer and more accurate descriptions of what is happening without making people wait. Just the general kind of combination of player attitude/maturity/competence that glyph mentions. Having a good partner makes it great to play off of other people. I also think that NOT having the gm around(like i said, weekly game) for interparty social actually helped a little bit - there was no potential animosity from someone ELSE stepping in to say 'this happens', and the dice are a neutral trustable party.
But when we used dice - and we did, fairly frequently - the one thing we used the most were Judge Intentions - to read what was going on - Con Checks(for lying, and having the other not notice), and, occasionally, Composure tests, for when something really strange or funny happened. None of this quasi-mind control social rolling crap. Having good character interactions, with the dice there as a sort of neutral adjudicator of 'what happens when...' happens to work out very nicely, and can occasionally lead the way to its own funny occurences. A good example from our game involves that kind of hilariously improbably dice luck that happens occasionally: the hacker and the face just could NOT lie to each other. They were both competent enough to not press for details, or cause a scene, or annoy the other person - over the course of multiple sessions, every(and I mean EVERY) time a Judge or Con roll was rolled against each other, the lie was spotted. Nothing was necessarily DONE about it, depending on the situation(nobody cares if you really don't like the coffee), but it was noticed.
And eventually we just stopped rolling, and started working the same information into interactions without the dice at all, just accounting for familiarity naturally in the course of play.
Just thought I'd share my experience with it. Worked out very positively, but I think the players are much more to blame for that. Rolling for Bullshit Checks(only), and letting the players act, react, and change the scene appropriately works out really well.
But it works out even better if your players can act their role well, too. An emotive, understanding, mature player who can bring that spark of life to a character is worth hanging onto, because they can make any game so much more interesting.