If they are saying it doesn't matter what faith they have then they wouldn't be criticizing Dawkins' beliefs. He certainly has faith in them.
Are you saying these liberals are saying they must be "theistic" beliefs? Could you point me to where this has been said to Dawkins? I'd like to see this actually being said to him to see what I hear reading it.
But let's be clear, Dawkins view on religion are in fact not liberal understandings of it at all. It's the fundamentalist understanding he always picks on. But furthermore and to my actual point, he is saying in effect, "No, I have the truth, and you do not! You are deceived, lost, and deluded, you and your God Delusion." And that, is the same behavior. That is the fundamentalist mind.