What is the "God particle"?
The Higgs field is a theoretical(not for long?) force which permeates all of the universe (much like the Force from Star Wars) and which gives certain particles that interact with it, such as protons and neutrons, mass. Other particles, which don't interact with it, such as photons and neutrinos, remain massless and move at light speed. The Higgs boson is the force carrying particle of the Higgs field, like how a photon carries the force of electromagnetic fields.
In effect this is what creates all matter in the universe by wrapping a bunch of energy (inertial and gravitational mass) into one point. It also has the effect of slowing down massive particles (like the proton and neutron) to everyday speeds (a particle with mass can never reach light speed). If the new particle discovered turns out to be the Higgs, boson this would indicate that empty space has a inherent energy in it. I suspect this will be a big step to understanding dark energy and a more coherent understanding of quantum gravity.
Here's a great cartoon about the Large Hadron Collider and what the Higgs boson below.* The audio sounds like it was mostly recorded at the LHC cafeteria (and the video starts off with cafeteria footage for the first 40 seconds so you might want to skip ahead a bit) but it is a really good explanation about why everyone is so excited about the Higgs boson.
What does this have to do with God?
Many scientists dislike the term "God particle" because they feel it has nothing to do with religion. Scientists in general like to stay away from religion so this is understandable, but because the particle is what creates all the mass, really the substance of matter, in the universe it has has a decent claim to the title the "God particle" and actually says a lot about theism.
First, it is further evidence that religions of the world had no more insight into the true working of nature than any illiterate caveman did. Although it was early science which developed many of the earth centered astronomic models, it was religion which froze them in mystical importance based on the "perfection" of the heavens. It is only when we can question old ideas that we are able to find more accurate and complete models for how our universe works.
Second, it indicates that important and consequential knowledge about how the universe works does not come from prayer or supplication to any deity. Perhaps God was not aware of this particle, but if so, that would hardly make him all knowing. Maybe he purposefully never mentioned it to and prophet or preacher he communed with. If he is trying to keep the knowledge from us, then why couldn't he stop the scientists at the LHC from discovering it? In the end, God is either a fool or powerless, or both.
What does the God particle's discovery mean for reason, logic, and empirical evidence? That with a focused application of accumulated knowledge, engineering, and commitment humanity can peer farther into the mysteries of the universe without God than we ever could with him.
*One thing they didn't really go over in the cartoon above is the gauge bosons in the Standard Model particle "periodic table." Here is a more complete version with the force bosons - photon (electromagnetic force), gluon (strong force), and Z and W bosons (weak force).
image source: http://en.wikipedia.org/wiki/Boson
