Jeff Jensen at Entertainment Weekly made the mistake of asking Lost executive producer Damon Lindelof a direct question: Will the show ever give us specific resolution on the Numbers? (4, 8, 15, 16, 23, 42) Here's what Lindelof said:

''There will be more ON the Numbers, yes. But explaining WHY and HOW they are magic is like trying to explain why some magic kids are born to two muggles. The Valenzetti Equation USES those numbers, but trust me, they were around LONG before the early '60s. But for fans waiting for an advanced dissertation on the mythic significance of the numbers, I direct them to Qui-Gon Jinn's speech to Shmi Skywalker regarding midichlorians and pose the following question: Happy now?''

Here's that speech, according to Wikipedia. It says Qui-Gon was talking to Anakin, not Shmi, however the hell Shmi was. I'll take their word for it, because the less time I have to think back on The Phantom Menace the better:

Anakin Skywalker: Master, sir, I heard Yoda talking about midi-chlorians. I've been wondering... what are midi-chlorians?
Qui-Gon Jinn: Midi-chlorians are a microcopic lifeform that reside within all living cells and communicates with the Force.
Anakin: They live inside of me?
Qui-Gon: In your cells, yes. We are symbionts with them--
Anakin: Symbionts?
Qui-Gon: Life forms living together for mutual advantage. Without the midi-chlorians, life could not exist, and we would have no knowledge of the Force. They continually speak to you, telling you the will of the Force. When you learn to quiet your mind, you will hear them speaking to you.
Anakin: I don't understand.
Qui-Gon: With time and training, Annie, you will. You will.

1) If you call a little boy "Annie," he's going to grow up to have some serious problems, and 2) We finally have official confirmation of something that many have long suspected: The Numbers are a load of horseshit.