I think the best part of the Alaska Airlines Mileage Plan is the wide variety of partners on which to accrue and redeem miles. Alaska is a great program to 'link' between airlines like NW/CO and, say, AA. As I fly a little bit on CO each year, a little more on AA and NW, and a lot on AS, I get to accumulate miles for all those flights in one program. Then I can go and redeem those miles on the above mentioned airlines or on Qantas, British, Lan Chile or Hawaiian.