There are different arrangements among different airlines. The UA *A is the most restrictive. No elite bonus except on translantic LH and no upgrades.
The AA OW arrangement is better. You get elite bonus systemwide but no upgrades.
The NW/CO/KL arrangement is the best. You get elite bonus, and upgrades systemwide. From what I know, only the NW/CO/KL arrangement is close to being "seamless". Too bad you have to fly NW to get it.
[This message has been edited by TerryK (edited 10-01-2000).]