Speak up and let your voice be heard. If you see a problem, talk about it: inequity thrives in the darkness, and the more places you talk about it, the more light you shine on the problem.
Too often, I hear people respond to the discussion of a D&D-related problem with "stop complaining and go write a letter to customer service." This is misguided. We should be talking about it in multiple venues, not just one.
In that vein, here's a pair of things I've sent to WotC that I have *also* said on the community.wizards.com forums, to my friendly local gaming store, to the twitterverse, and face-to-face with my friends.
Support for people with disabilities:
Hi, are the D&D Encounters events wheelchair-accessible?
If the venues that host D&D Encounters are not required to be wheelchair accessible,
...
