Not a concern.
My father-in-law is an exec with Saudi Aramco (the Saudi government entity in charge of drilling, processing and selling oil to the rest of the world), he's been out there for 30 years.
In the '70s the Saudis were saying there was only 40 years' supply left. They've got over 300 new wells in process at the moment and they're saying now (2007) that they've got over 50 years reserves at the current rate of demand - and still over 90% of the country hasnt' been explored with the new ultrasound exploration techniques that have only really been perfected in the last few years.
They've always known since way back in the '50s and '60s that there were thousands of smaller oilfields and prospects further inland and to the south of the country, but it was never economically viable to drill them at $25 a barrel. At $65 a barrel all of a sudden it makes a big difference.
So yes the oil will outlast our lifetimes. And turbine engine technology can be adapted a lot more easily to alternative fuel sources than internal combustion engines, when the day comes that it does eventually run out.
The greenies will put us all out of business long before the oil runs out (here in Europe anyway), that's the real concern you should be worrying yourselves about!
