Transparency is a great idea. May I suggest starting off by releasing your intended feature list for the product? That way, with each release, you can cross things off the feature list, and people can see that you're making progress.
Going to disagree that this is a good idea. One of the worst things you can do is release a product "road map." It makes expectations way too specific, and will put you in the position where if you need to alter or change that roadmap you are going to get pre-emptive backlash for work you have not even done yet.
