I'm looking at a probable trip next week from DTW-LAS. I normally fly CO through Cleveland or IAH but the rates are extremely high. I'm used to paying between 250 and 500 for that flight every 4 weeks or so, but the fares next week (probably due to Easter) are well over 1,000 for economy. I never fly other airlines in the U.S. so I'm curious as to how I can fly a partner airline and still receive my Platinum Elite miles and upgrades.

Out of DTW Northwest is the big airline, so I found lower fares through them. If I book online on NW's site, and provide my FF# will I receive the Elite miles? What about upgrades? I know CO upgrades NW customers b/c I often meet them in First Class. But does NW do the same? Do they upgrade the same way or do CO Plats only get upgraded after all Elites on NW are upgraded?

The way it is worded on the website is a bit confusing- could anyone else shed some light on this for me? Many Thanks!