Does God exist?

With the release of the movie "Religulous", Bill Maher and Larry David have waded into the debate about whether God exists. Bill Maher claims that his movie is really about challenging the certitude of religion. However, it is clear that he doesn't believe in religion or God. The question is, should we?

The question "Does God exist?" is suprisingly difficult to interpret.

To begin with, what do we mean by "does"? Does has a temporal connotation. But, what time is relevant? For instance, starlight reaching earth often comes from stars billions of light years away. These stars may have burnt away or exploded many millions of years ago. Yet, their light has only just reached us, and to us, they exist. But do they? Is it sufficent that they did exist? What time is relevant?

What do we mean by God? Are we interpreting God to literally be the God of a particular religion? Or do we mean the general concept of God. And if its the general concept of God, what is that concept?

Also, what do we mean by exist? What exists? Do thoughts exist? Does the Wonderland described by Lewis Carrlo exist? How do we know?

These are tough questions. There are no specific answers. But over the posts here, I'll explore what issues the answers would need to address.