The average opinion appears to be:
The spike to $150 was a financial abberation,
but one that came about due to
a)The boom in global economy - coupled with
b)Peak Oil fears entering mainstream economics.
The current drop in price is entirely due to demand destruction in the recession.
Wild swings of high and low
prices and
demand in chaotic feedback are
symptoms of the peak. Without the capability for continuous growth, the oil market 'bounces' against the ceiling.
Ultimately, a crash in oil prices is
bad for the peak, because it reduces investment in the projects which are supposed to soften the decline rate.
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As for what's going to happen, the numbers (that I've read about) show that replacing oil as an energy source is beyond our current industrial means. ie. once we're over the peak, it will not be possible to manufacture enough windmills, nuclear plants, biodiesel refineries etc. to offset the decline. So yes, a decline in 'living standards' is, as far as I can tell, inevitable. However, that decline will not neccesarily be uniform accross the globe. Whether or not the 'farming of suburbia' will ever happen, a reversal of globalised capitalism will happen first, with countries less willing to share their energy reserves (or access to those reserves. ie. the US didn't build that massive embassy in Iraq for nothing...)
That's just a ramble off the top of my head though, so please rip it apart
The only prediction I'd like to make with any certainty is : we will never pump more than 100,000,000 barrels of crude in one day.