The questions like "Why should we trust you?" seem to me like an attack on everybody's intelligence: I will bullshit a little bit why you should trust me and then you will trust me that you should trust me. So, thanks, but no, thanks.
At the other side, Lodewijk's question is my favorite one, as it addresses the complexity of the relations inside the movement.
I will start with the mantra: "We are one movement!" -- because we should repeat it to ourselves whenever we come into the seemingly unsolvable conflict. Not just one side, but both, all of the sides should remember that!
We could have quite opposite, different views related to the [real world] politics, even to the vision of our movement today or in the future. However, the power of the idea that knowledge should be accessible to everybody, the power of people following that idea, the power of our movement, that power makes those differences insignificant.
A person can't say for themselves that they are a Wikimedian if they haven't successfully survived numerous cultural shocks while doing Wikimedian tasks -- online or offline. A lot of our first contacts were initially catastrophic. But we've survived and learned how to get along. (Yes, especially you and me, Lodewijk :) )
That cultural trait is one of the most important strengths of our movement and we should nurture it.
But it's about culture and lack of trust is not just about culture. Culture helps us to have better communication and to heal our wounds more quickly, but lack of trust is about much more realistic things: it's about mismanagement in communication, it's about real or perceived opposite interests.
The general answer related to the "real part" of the trust issues is in the fact that the most responsible for building trust are those in position of power. While it's sometimes hard to define who is in position of power, in the most important cases it's obvious. Yes, Board members are in the position of power towards anyone else inside of the movement. Yes, chapters are in the position of power in real life towards the local communities. Yes, WMF employees are in the position of power towards the vast majority of editors. And, yes, and so on :)
Speaking in the most general terms, we should build the system to check the power. We should openly talk about it, that should likely be a set of Meta pages, where everybody could come and raise the issue -- not exclusively about power abuse -- but about power that should be checked.
But many of the issues are much more simple. We could easily see that there was a time when the Board flagrantly forced the perceived interests of WMF in confrontation with chapters, in confrontation with community, in confrontation with employees, even in confrontation with the fellow Board member.
We could easily see the stratification of our movement even now, during these elections: it's mostly obvious which candidate has been supported by which part of the movement. However, that's not explicitly noted anywhere. We are living in the limbo in which "everybody" knows more or less everything, but "nobody" is willing to talk about that openly.
That's because not all of the voices have been articulated. Not all of the movement factors are able to express themselves clearly, to be heard proportionally to their contribution to the movement.
Those in the position of power should understand that it's their interest to hear organized and articulated voices of those not yet represented in the dialogue because unrepresented voices lead to distrust and consequently to dysfunction.
How to solve that? Organizational articulation of unorganized parts of the movement would definitely help a lot. However, we could start doing that even before the completion of the process: Let's start talking openly! Let's not avoid the real issues! Let's think together how to address real issues that bother us and our fellow Wikimedians! Let's address them!
I am sure that opening discussion and showing that addressing the issues is going at a reasonable pace -- would immediately lower the tension and distrust.
But, again, whenever we come into the conflict situation I would urge everybody to use the culture to start overcoming the problems: We are one movement!