What's interesting, is that this is what should happen. Since Bitcoins are generated at a constant rate (from my understanding) regardless of how many people are working on them, the market should eventually even out so that its a break-even at best. Likely it will be a little worse than break-even, because there are always some people out there willing to attempt to generate coins even if what they are doing doesn't…
I'd guess that the percentage of miners and speculators in the BTC market who are economically irrational in their activities is a lot higher than most of us think it is. Ergo, I don't place too much faith in any models, theories, or projections about this market that lean heavily on assumptions of rational actors.
Following from this logic, I can't justify taking a significant position in this market. The risk is enormous, and as risk goes, it's not incredibly attractive compared to alternative investment vehicles or strategies.