Is there a particular attraction to buying a codehsare that I am missing though? Particularly for CO/NW. It's not like you'd be able to get 100% EQM on NW metal just by booking on CO.com right? So why does it matter so much if your NW segment has a CO flight number? My corporate travel dept could care less. I feel I am missing a big point of booking the codeshare that people here want...anyone help me understand?

My only problem is I'd like to stick to CO.com's interface, but NW's doesn't kill me. It's a heck of a lot better than flying SEA-IAH-MSP when the NW flights between SEA and MSP are all CO codeshared but unbookable.