Does this statement even make grammatical sense?
First of all, "Atheism is a faith in that which has not been proved...." Um, no. Religions believe in things that haven't been proved. Theists are the ones with faith (equivocation warning!!!). I am an atheist because I don't have faith. I'm an atheist because I only "believe" in things that can be proved. I worked at trying to find faith for a long time, many years, and I just don't have it. I see a statement like this and I'm forced to conclude that this poor theist is either confused or projecting.
Secondly, it's not a matter of "witnessing" anything to believe in, and theists have witnessed something to believe in. The problem is not in seeing, it's in the interpretation. I'm seen some pretty amazing things, but I prefer to understand them, or to simply marvel at the mystery, rather than jumping to unfounded conclusions.
Lastly, the fact that there is no 'good news' to preach in atheism is beside the point. One could consider it the most dreadfully depressing news a human mind could conceive and it would not alter it's truth value. The same can be said for the reverse proposition. The 'good news' that religion claims to preach is not true simply because it's good. Good/bad, true/false are not interchangeable. Indeed, in my experience, the truth is often uncomfortable and unpleasant.