@pokey: the mandate of the USGS report was to assess the amount of oil recoverable using today's technologies, not possible future technologies because unless they are being rolled out now, they won't help push off peak

Also, the USGS has a demonstrable inability to project realistic oil numbers and Dave Cohen's piece at ASPO USA's site discusses why that might again be the case here.

http://www.aspo-usa.com/index.php?option=com_content&task=view&id=355&Itemid=91

Last, our immediate problem is how quickly we can get new oil to the market and because this formation is classified as "unconventional," that == not quickly. The Bakken formation will not push off peak.

It's also good to be reminded from time to time that each billion barrels of oil pushes off peak by only 6 days. We are currently using about 85 million bbl / day.

1 000 000 000 bbl / 85 000 00 bbl/day / 2
= ~6 days

So the 4 billion barrels, were it to quickly get to market (not possible, it's not conventional oil), would push off peak by approximately 24 days.

-André