I agree with contortionist that it's a bit of a mixed bag. On the one hand, I think he is right to say that atheists don't have a faith in the sense that they believe in something that can't be proved - that is, the non-existence of God. On the other hand, that whole squabble about who can prove what depends on a conception of God that is simply not what Christians actually believe in. As Rupert Shortt has argued, in his book God is No Thing, to see God as an entity within the cosmos whose existence could be found to be somehow separate from the cosmos is to fundamentally misunderstand the nature of God. For Christians, God is outside the cosmos, outside space and time, and the cosmos and space and time are God's creations. He is the uncreated creator, the first cause - the thing that causes everything there is to be - who is himself/herself not caused by anything. To prove the existence of God using the methods of empirical investigation - which is what you would use to look for the evidence of the existence of an entity within the cosmos - is not only fruitless, it's the wrong kind of search. It's like using a microscope to look at a giant, or trying to dissect a poem in the large hadron collider. Sensible though he is in some ways, Baggini seems to me to be stuck in this wrong conception of God - the conception that underlies Bertrand Russell's stupid flying teapot analogy.
So that's one thing. The second thing is that while imputing unprovable metaphysical beliefs to theists he seems unaware of (or perhaps unwilling to admit to) the metaphysical aspect of his own position. To say that there is no purpose to the world, that the universe is indifferent, that life has no inherent value is to make metaphysical claims - that is, claims that cannot in the end be proved by empirical means. This is one of the things that theists often mean when they say that atheism is a faith position: that the underpinning ideas which bolster atheists' convictions are essentially metaphysical not empirical. To say that there is nothing beyond the material is to make a claim about the nature of reality that cannot be proven, and to make some assumptions about what 'being' or 'existence' or 'causation' is that go beyond the reach of science.
Thus, as he says in his last paragraph, atheists need recourse to things that are beyond the reach of science. He finds this in the 'beauty and joy of life', which is essentially a form of pantheism; and in 'the empathy that makes us see value in the lives of others', which is a central tenet of modern humanism. And that is all very well, except it has nothing to say about suffering - what happens when there is no joy or beauty in life? - or about evil - what do we say, then, about our capacity to reduce others to objects for the satisfaction of our cruel impulses? You may well consider the Christian response to evil and suffering to be inadequate or obnoxious (I would disagree, but that's another conversation) but at least Christianity has one, which pantheism and humanism manifestly do not. When he says that 'the beauty and joy of life' and 'empathy with others' are not matters of faith, I part company with him. It's not that I don't think there is a lot of beauty and joy in life, or that empathy exists - but to see them as the 'ground of ethics' seems to me to be a statement of faith which forms a kind of atheist dogma, one that can only be maintained by ignoring large parts of reality.
On the other hand, I think he is trying to get beyond the crude scientism of some well known atheist crusaders and that appears so often on MN. That can only be a good thing.