For reference oil prices above $100 render the airline industry as dead as a dodo. Never mind $110, $120 or worse. The last time any airline was profitable was doer and gone at $80.
Wags now openly speculate on the survival odds of one carrier or another — Midwest, Frontier (already operating in Chapter 11), US Airways, Sun Country and Spirit seem to be popular picks in death pools — I wouldn't assume any carrier will fold. Or survive. Know your options for every flight you book. And carry your Plan B and Plan C with you in case your carrier folds while you're on the way to the airport. Seriously.
Stop “banking” frequent-flier miles. If you've got enough miles to claim an award, use them now. The value of miles is depreciating even faster thanks to the route cutbacks and new fees imposed when you redeem an award. Besides, if your airline collapses, there's no guarantee that another carrier will step in and honor unused miles.