So I feel like I may be stepping on Alto's toes, or just being unoriginal, posting about the "Pyrite Stockpile" right after he did a rather excellent write up (see, Epic Gems in Cataclysm), but I believe I have a unique view on the whole debate that I would like to share in the hope I can bring people over to the stockpiling side.
The gold making community is divided between those of us who think epics will come from Pyrite ore, and those who think Blizz will take a unique route. There are excellent points on both sides of the debate; some argue Blizz will go with the tried and true method of prospecting for epics, as that ensures JCs will be able to get them, others say that there's no real precedence for prospecting as you couldn't do so in BC, so Blizz might decide to go with a third, wholly unique option on how to get the gems. Honestly, I think these arguments are irrelevant.
Look at it this way: either Pyrite will prospect in to epics, or it won't. There's no third option. Likewise, you'll either stockpile Pyrite, or you won't. No other alternative (even keeping a few stacks counts). That leaves us with four possible outcomes when epic gems are released:
1) Prospectable Epics + Stockpiling
2) Prospectable Epics + Not Stockpiling
3) Not Prospectable Epics + Stockpiling
4) Not Prospectable Epics + Not Stockpiling
Scenario 1) is obviously the best. You've stockpiled and it's paid off big time. You will be rolling in gold. This is what people stockpiling are hoping for. Scenario 4) is purely neutral. You gained nothing, and you've lost nothing. This is what people not stockpiling are hoping for. Scenario 3) is what those of us stockpiling are dreading. All that gold we sunk turns out for naught, and we're left with bank tabs full of "useless" Pyrite. But wait, it's not useless! Pyrite still has some excellent prospecting tables, and we're likely to recoup a large chunk of our gold through the normal channels. Scenario 2) is what those not stockpiling should be dreading. Turns out that epics do come from Pyrite and you've totally missed the boat on this one.
The way I see it, the worst case scenario for those not stockpiling is much worse than the worst case scenario for those stockpiling. By not stockpiling, you are risking not making what will likely be an obscene amount of gold. By stockpiling, you're risking losing *maybe* half of what you have chosen to invest (given the downward trend in prices of Vol. Earth and Rare Gems). But if you buy cheap enough, you can probably cover a good portion of your potential losses.
The difference is that the loss those not stockpiling are risking is an "opportunity cost" loss, i.e. they're risking earning potential, while the loss those stockpiling risk is an actual loss of wealth. This is why I wouldn't recommend sinking a substantial amount of your wealth in to this risky venture. However, if you can tie up a few thousand, ten thousand, or hundred thousand investing in Pyrite Ore, the potential reward vastly outweighs the potential loss.
This is certainly a matter of personal preference, but as yourself this: When we find out where epics come from, would you rather be kicking yourself for not stockpiling Pyrite, or kicking yourself for stockpiling Pyrite?