I've heard about this before, there are two big drawbacks though.
1.) The cost effectiveness of extracting the oil. When gas hits $5.00 a gallon it would be more cost effective to tap into these reserves. At the current rate of approx $2.00 per gallon there is no profit, hence no incentive, to go after these reserves.
2.) There are the environmentalists to contend with. They have the, "not in my back yard attitude," that pretty much kills the profitability of extracting this reserve as it would cost too much to deal with their incessant lawsuits, injunctions, and of course the endless court appeals that could drag on for years.
If and or when foreign oil reserves begin to dry up, and the price of gas skyrockets to the $7.00 per gallon mark, maybe there will be enough public support to squelch the outcry of the environmentalists, and get down to the business of securing our future.
Then again, by that time, alternative fuel sources could break through the technological barrier to profitability making this whole discussion moot. Realistically I don't see that happening within the next twenty five years.
Just my 2 cents worth.