I think now is the time to accumulate miles via credit card bonuses and spending. AAdvantage/Citibank has a great offer, Delta/Amex has a very good offer, and NW/US Bank has a good offer. I would never try to leave more than a round-trip for the family on the table with each carrier, though. I was convinced there wouldl be many bankruptcies in the airline industry in 2009. With oil dropping fast, they may be spared, but if oil reverses, there is no way for the airlines to weather that storm, except for a few, like Southwest. I'm only a leisure flyer, once a year or once every two years, so I make sure I never pay for a flight or hotels for my family. I have a round-trip for 4 built up on Northwest, so I will use that next. I have a round-trip for 4 built up with American, and I can convert that to Priority Club if need be. I have a pair built up with Delta, and will hopefully merge those with some leftover Worldperks miles once they merge. I also have a pair of United for me and the wife. I have a lot of No Hassle miles as a backup too. So, considering I have enough flights saved up for the next several years, I don't want to go too far just in case of bankruptcy. So, I'm switching my focus to building on my hotel base now. This is a much more stable industry, and I'm more confident of their ability to survive a down economy.