Let's look at a couple of representative interaction with the fanbase.
Love it or hate it, PvP, like PvE is large part of why people play MMOs. Currently PvPers in SWTOR are pretty unhappy with the state of PvP. (See http://www.xamxamsays.com/?p=1473 for an excellent post about why folks are unhappy with PvP).
The combat team has been trying to interact with the PvP community and explain what they are doing. Recently they explained their thoughts http://www.swtor.com/community/showthread.php?p=8122355#edit8122355 on the success of Sentinels/Marauders. They followed up with http://www.swtor.com/community/showthread.php?p=8127209#edit8127209.
Reading these after the fact it looks like a reasonable position. The problem is that the second post is two days later. If combat team had posted those two items as a single post with a sentence saying something to the effect 'That's where we aim our balance efforts (win/loss ratio), but we understand many of you look to the leaderboards for evidence of overall class balance…' they would have headed off much of the two days of vitriol.
Bioware has to be the ones who connect the dots from how they view things to how the fans view things. By saying, yes, we see that issue too and are working to change it for the better Bioware acknowledges the concerns of the fanbase (and demonstrates they are listening to the fans, to boot!) No fanbase is going to like every answer, but when you are listened to you have a reason as a fan to stay engaged with the communication instead of just grumping about everything.
And, yes, talking about the leaderboard situation might be a bit Captain Obvious and repetitious for the combat team, but repetition is crucial in communicating with your fanbase. You never know when any particular fan is paying attention so you want to make sure you keep your messages out there.
Depending on your point of view, the cantina event at Star Wars Celebration was either a success or just another Bioware screwup. Given the event was designed to promote the game, Bioware did a poor job of communicating what they would be talking about to they most-engaged fans.
It would have been much better if they had stated something like, 'The SWC cantina event is for us to promote the coming patch (3.2) to the wider Star Wars, non-SWTOR-playing audience. There will be a few new things, but don't expect to see any huge reveals at this time.' That alone would have helped set expectations properly for the engaged fans. (The fans that read the forums, follow blogs and websites, listen to podcasts, watch the videocasts and Twitch/Hitbox streams. Basically, your front line influencers/tastemakers.) Knowing that Bioware was using the event to try to expand the player base would have given the engage fans a chance to help out. As it was, the lack of knowledge simple stirred the dregs of disappointment as Bioware 'failed' to wow the existing involved player base with a cool roadmap.
That disappointment then bred cynicism with the Q&A portion of the event. While the questions weren't supposed to be vetted, they certainly gave the appearance of vetting. Vetting to the point of hearing the same questions asked once again (playable Wookies, anyone -.-). Whether or not the questions were vetted, Bioware should have announced that they did vette the questions. Vette them to add hard questions. If you are going to be accused of something, make it work for you.
Here's a couple of questions the fanbase perceived as hard and that were vetted out of being answered. I've included hypothetical answers;
[Hard question]: PvPers haven't had anything new in over a year. Could we at least get a new map? We've shied away from new maps because we didn't want to reduce the chance of you getting your favorite map. Until we can implement a solution for faster queue pops we don't want to mess with PvP in a possibly negative manner. If you want more maps with the risk of seeing the ones you like less, please sound off in our forums on the issue.
[Hard question]: Why are we getting an Outfit Designer when we have adaptive gear? Why not make everything adaptive and just give us a real Gear Manage instead? First, making everything adaptive would require us to go back and redo the rewards for all of the old quests. That's a non-trivial amount of development time that we prefer spend elsewhere. Secondly, we want to do a Gear Manager. If you considered the Outfit Designer as a first step to seeing what kind of load such a system might put on our databases then you might be thinking like we're thinking. That said, we've had many requests for the ability to use non-adaptive gear for cosmetic purposes. While recognize this adds yet another cosmetic system, this was the easiest way for us to go, development-wise.
Again, dealing with questions the fanbase thinks you are going to just ignore is a great way to start building credibility again.
From the fan base, a goal should be to continue to talk about improvements fans want in the game including possible solutions. While folks are frustrated at many parts of the state of the game, being constantly negative just gives the developers and the community team the excuse to tune you out. Be fair, if they get it right, say so. If they make a mistake, say why it is a mistake without being person. There are enough trolls in the forums, don't be one. A critical, but fair fan is more likely to rise above the noise of the trolls and have their signal heard.
Suggest solutions to problems you see. Bonus points if you explain why the solution is a win-win for both sides. Bioware is going to expect any solution a fan makes to be a win for the fan – it takes an unusual fan to suggest a needed nerf – but a fan that can show how the solution helps Bioware gives ammunition to the community team and developers to push through changes. Yes, Bioware may have already considered the change themselves, but when can point to community support and acceptance of a possible solution the effort needed to 'sell' the resources required to implement a change becomes that much less.
From Bioware, more openness. Let us know if a cantina is going to reveal new, major information, or if it is going to be aimed more at casual player. (Engaged fans tend to seriously underestimate the lack of knowledge the casual player has about upcoming changes.) Explain why you do things from a developer perspective, but always, always, ground those explanations in what the player base is looking at.
If you want an example of what can be done, just look at what Greg Street (Ghostcrawler) did for Blizzard. His willingness and tenacity at engaging in a much larger, more vocal fan base changed the tone and amount of interactions Blizzard has with its fanbase. It wasn't easy, it took a lot of time, but engaging with your community pays huge dividends. Dividends a smaller MMO can't afford to miss out on.
 Remember the basics you learned in Speech class where a simple speech should be in three parts? The first being about what you are going to talk about, the second being the talk, and the third summarizing what you talked about. The idea is to be redundant with your communications because you can't tell when someone will be paying specific attention to what you are saying.