aislesonly,

Yes I mean codeshares for the CO metal portion. Specifically I flew on a NW ticket (with NW flight numbers) MCI-IAH-DEN-IAH-MCI (both segments CO metal obviously) and have received to date:

5/19/01 Non-Travel DOUBLE MILE BONUS 657 657
5/19/01 Non-Travel DOUBLE MILE BONUS 876 876
5/19/01 Air CONTINENTAL 0587 XF IAH DEN 876
PLATINUM ELITE BONUS 1095 1971
5/19/01 Air CONTINENTAL 0605 XF MCI IAH 657
PLATINUM ELITE BONUS 821 1478

The return has not posted yet. I cannot speak to the issue of CO tickets on NW metal, but I suspect the answer is that you won't receive the bonuses. Others have stated this in the past, but I'm not sure if it was based on actual flights or only speculation.