(Clearly the more dangerous move here was the price hike, but I do not know the internals of the company that led to the decision, or the interest that it was in, so I will not comment on that so much.)
It is tough to imagine them recoverving from the sort of mob-rule that has formed in that comment thread, even if they restore current pricing plans. So much doubt was created amongst the users, which of course spread to twitter, here, and others, and you can see the discussion clearly degrade from concern to rage.
Public interaction with users can be helpful to show a personal side of the company and try to show a strong effort for support/interaction, but do not forget that this risk exists. As with anything, use with caution.