One of the common mistakes that 4E DMs make when using skill challenges in their adventures is that they often turn it into a plot road block. They expect their players to be able to overcome the challenge or else the pace of the adventure would grind to a halt.
One of the easiest way to counteract this problem is that DMs should look at the consequences of the skill challenge from both sides, whether the PCs succeed or fail. In the recent D&D podcast on skill challenges, the designers agreed that success and failure of skill challenges shouldn't be used to sink or swim a party from moving on. They are meant to be a challenge which should not deter the story from moving forward but move it into different direction either way whether by defeating the skill challenge or not. In most cases where a skill challenge is concerned about getting from point A to point B, a success could mean a smooth transition to the next step of the plot while a failure could eat up more resources or lead to a longer detour to reach the same point.
That's one way of looking at it, however, it's a very narrative approach and it does take a little thinking ahead on the part of the DM. While the idea of giving skill challenges a sort of objective where success and failure is a matter of how to get to that objective, it means that a DM has to think of 2 solutions to the same problem.
While it is certainly a reasonable method of making skill challenge feel more like a challenge than an absolute barrier but I find that embedding a reward and punishment mechanism isn't a fair way of seeing it. I don't think that a skill challenge should only reward successes and punish failures. Skill challenges should also be more like combat which is a common analogy of how a good skill challenge works. Although the PCs flee from combat but managed to defeat a few minions or sneak past them entirely, they still deserve a small share of XP from that encounter. Even if the PCs didn't intend to lose or run away from combat, at least they are still rewarded for their prowess and discretion all the same which makes them feel less horrible about themselves for not being able to defeat that encounter than getting a TPK.
So, the question is why not do the same for skill challenges?
What I am proposing is a much simpler but more mechanical way of giving the same feel of success and failure of a skill challenge without disrupting the flow of the game while at the same time not destroying their morale for failure. Give XP reward for accomplishing a skill challenges regardless of whether they succeed or not. Whereby, a DM would let a success lead to a larger amount of XP reward than a failure but either way it doesn't really punish players for failure. XP rewards could also be bigger the more complex the skill challenge is. This will cause the players in their mind to try and get the best results without having to worry whether they will succeed or fail the skill challenges. One benefit of this method is that you only have to think of one narrative solution to the same problem because the outcome would still be the same but it is a measurement of the degree of success.
Other ways of playing around with this idea is to distribute small XP packets to certain success gained from using certain skills. Make skill challenges look more like a grab for XP until they reach the maximum number of success or reach the minimum amount of failures. This may encourage the usage of primary skills over secondary skills in a skill challenge if the DM prioritizes certain options more over others. This can add a different dynamic in playing/running and designing skill challenges which might test the wit and resources of the players more than the PCs. There is more of a cost-benefit element that players will have to consider when undertaking such a skill challenge where they will have to decide if the risk of failing the skill challenge outweighs the XP reward behind it.
Another benefit of rewarding XP in skill challenges is that it becomes another source of character advancement. If you are having trouble with the idea that the only way for players to gain XP in their adventuring career is only by beating tougher and tougher monsters, skill challenges is most certainly a valid avenue to get XP for the less combat inclined characters. At best, this might put back some roleplaying into an otherwise combat-oriented game where it's not always about using swords to improve your character.
So what do you think? Will this idea work? Does anyone want to playtest this and share the results?