I came across this article on the Washington Post's website today and I was curious how credulously I should treat it?
In summary the article challenges not only the historical existence of Jesus, but also it challenges the methodology used by religious scholars to prove both this and other claims found in the Gospels.
I'm no historian myself, but I'm somewhat familiar with the problems that historians have when trying to identify individual historical figures from this period. However I've always found the argument that we shouldn't necessarily expect to be able to find details about his life in the historical record to be a bit troubling, or at least unsatisfactory. Given the somewhat extraordinary claims that are made (even without the supernatural elements of the story), the fact that according to the narrative he was politically dangerous enough to warrant execution by the state, and the degree of deference that scholars appear to offer to sources which clearly have an evangelical agenda it doesn't quite add up to me.
For reasons of basic logic I always feel drawn back to a more agnostic view that he may have existed, but that there's no real reason to assume that he did any more than any other semi-mythical figure from two thousand or more years ago but my sense is that this is not the consensus among professionals who study the topic.
My impression from previous discussions of the topic is that the consensus around these parts is that Jesus did exist even if the stories have been embellished, and I'm curious to hear specific rebuttals to the points made by Lataster in his article, especially as I am not familiar with him or his work and have no sense of whether he is considered an expert on the topic or if he's just trying to muddy the waters to promote his book...
While you wait for a rebuttal or discussion of that particular article, you may be interested in the section of our FAQ on the historical Jesus. It should answer some of your questions on historicity and the standard of evidence that's applied to figures of Jesus' stature.