If less than $300 RT - then buy now - for any destinations in the USA. If the price is high - say $600-800, then I would look at the seat maps - and if they are wide open - then I might wait - otherwise you might have the best price now.

I think you will see airlines cancelling flights and consolidating traffic before they start to significantly drop fares - based on today's situation (high fuel prices). And it could get worst - there could be a panic and things start to shut down (did you see the CNN show last weekend on what happens when oil goes over $200 and gas goes to $10 a gallon.)

Gasoline is already $10 a gallon in parts of Europe. Gas is $0.45 a gallon in the middle east. Could be that the Middle East airlines - like Emirates take over as the new world carriers as others go out of business.