Apples vs. Oranges. People are comparing NW '05 to UA '04. Wait until the other airline plans have been released before making any decisions. Assuming there will still be some differences between them perhaps the best policy is to book the largest number of flights with the carrier that is most convenient / best schedule / or with the best package of bennies, but accrue miles on a second carrier for that award flight (Australia/Europe).

People are also comparing carriers as if there was no difference in the likelihood of the failure / liquidation of each carrier. NW, with the new pilots agreement and anticipated debt reschedule, is relatively strong compared to for example UA. Unless you are planning to earn and burn miles within a short period, a more favorable schedule would be worthless if the carrier fails.

For my requirements, NW offers the schedule and pricing that is better than other carriers and the Worldperks plan is best for me. I think I will be making WP Silver this year after a four year absence. But I will be taking notice of the reduced miles on other carriers (UA) for Australia and thinking about how I might pick up some miles on them.