Welcome Draco. Nice first post, you raise an interesting question.
The very long-term picture seems inescapable. The earth's current population is not sustainable without petroleum. Therefore a population collapse seems inevitable.
The nearer-term transition period is debatable. I don't believe our civilization will just 'roll over and die'. I think many of us underestimate the power of revolutionary change. We tend to assume oil demand is inelastic.
I think oil depletion can be successfully mitigated for a long time, in fact there will even be some positives; like a cleaner environment and numerous economic opportunities.
For instance:
-consider gasoline demand. Simply reducing the speed limit back to 55 mph would save billions of gallons
ConocoPhillips Link
-think of the millions of commuters who drive back and forth to useless jobs.
ABC Corp makes widgets. But how many employees commute to ABC? The Systems Administrator to maintain the network. So the Exchange Administrator can provide email. So the Business Analyst can fire an email to the Systems Analyst (rather than get of his arse and walk over). Who in turn consults the DBA who works with the Team Leads, Web Developers and Testers.... on it goes. None of these people are involved in the task at hand, making widgets.
-the advertising industry can go. I don't need network television commercials to tell me I need to buy Colgate toothpaste. My mommy taught me to brush my teeth. When I need toothpaste I know where to find it.
-don't think a cataclysmic paradigm shift is impossible. In one decade computers and the I.T. industry revolutionized business. Oil depletion will force drastic changes in the way we work.
-consider real estate agents, investment bankers, lawyers, mutual fund salespeople, stock brokers, etc. What do they contribute towards our basic needs of food clothing and shelter? All of them will hang up their hats and stop burning gasoline to and from the office.
-just as the great Warehouse on Wheels (Walmart) destroyed Main Street America, we will see a revitalization of local tradespeople and community markets post peak.
How many homes today have sewing machines in them? Who needs to sew curtains when I can go to Walmart and buy petroleum (PVC) miniblinds for $20/window. We will need seamstresses, tailors, cobblers, carpenters, cabinet makers, glaziers, furniture builders, locksmiths and you name it. Currently we live in a throwaway society. Don't fix it, replace at Home Depot/Walmart
-forget the 2000 mile Caesar Salads. There will be a huge need for locally grown produce, creating enormous opportunites.
Don't get me wrong, I'm not one of those corny-copians. Peakoil spells the end of our society as we know it. But at the same time a balanced view is needed. Peakoil will surely have some silver lining to it.
Just my $0.022 (CAD)