One of my favorite topics. I'll give you my nutshell view.
I don't think we need to get anywhere near peak oil to begin the downward spikes, which I also think delays the onset of the actual true peak, or even if we pass it, it is run-out that really matters. One thing I've found out is that linear projections never stay linear for long. It's a highly dynamic and highly nonlinear problem. There have always been big spikes and big declines during and after approaches to this prognosticated catastrophy. Is it a coincidence that each oil price spike is followed by a more and more relatively severe economic decline. We don't have to get close to peak oil, only close to unaffordable oil... an "economic peak", if you will. The resultant decline in the world's economies, as they absorb the price increases, extends the time until the next relative economic peak occurs, and extends the time to the true physical supply peak as well. Another factor is, as long as oil is priced in US dollars, that means unaffordable only until the USD inflates enough to make the previous peak's price affordable again. Unaffordable oil brings the problem of peak oil closer to home and I think, makes it more of a risk. I also think that the true underlying scarcity will support a relatively high price even during the decline. I think we have seen some evidence of that this time. The price has held relatively high in comparison to when it plunged to $6/BBL in '86 for example. Previously, peak prices have resulted in severe declines in oil prices that have not happened this time, so far, "nock on wood".
Peak oil/runout has another scenario that does not require that we actualy reach it. We only have to get to the point where the exporting countries start using up their current export capacity in domestic consumption. That will happen in many countries relatively soon. It has happened in Indonesia, a previously exporting country now consuming most all of its own production. Keep your eye on Russia. When the have's don't have enough to export, "peak oil" arrives in the have-not countries. Keep your bag packed, you will probably be working in a "previous member of OPEC" country.
Further risk is to be found in the risk-reward scenario of exploration, which may accelerate the decline of supplies. It is relatively apparent that large oil field discoveries are becoming less and less frequent. The fruit is getting higher.. and smaller. When the probability of finding a paying strike becomes less than the affordable, reward price for bringing it in, nobody is going to go looking for it. That might turn into a scenario similar to just a handfull of old hermit prospectors picking over the mine tailings in Death Valley looking for the mythical mother load. How scarce does it have to get to where it won't support the exploration industry. That implies that, even if they go looking for it, there will be less of them that can afford to take the chance to find it. Probably that will extend the time to the actual true peak as well, if not the runout point itself. Whether you can make a living at it then... hard to predict.
To distill it down to what really matters at an individual's level, I think if you become damn good at whatever part of this you get into, there will be a place for you somewhere... and ... keep the parachute handy.
What was your college major, PE, or something else?
Only put off until tomorrow what you are willing to die having left undone. - Pablo Picasso
