New Atheism

Given the recent wave of 'New Atheism' as people seem to be calling it, I figured I would start a controversy here.

First off lets give some background literature, but I think most of you are aware of these already. Wired Magazine's The Church of the Non-Believers article, Sam Harris (End of Faith and Letter to a Christian Nation), and Richard Dawkins (The God Delusion).

Depending on your semantics I am either an agnostic or atheist. I personally agree with Dawkins' argument about the improbability of a Judeo-Christian-Islamic God or any other all-powerful, all-knowing being. Due to natural laws and processes (evolution), intelligence in a system occurs late. Therefore (I'm greatly simplifying his argument) it is unlikely that an intelligent designer caused the universe to begin.

While Dawkins' primary point is that God is very improbable, Sam Harris argues that we should challenge beliefs that have no evidence. By not questioning these beliefs people can undertake bizarre and even harmful behaviors because of them, such as terrorists killing themselves and others because they believe they are going to a better place.

So now to the highly offensive question of the year. If you do believe in a god, why? If not, why?

The second question: Should we challenge other people's beliefs that cannot be backed up by evidence? Is this a good policy for a society?