<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by number_6:
This is a CX service. I believe it is only if you are flying CX to NRT, doubt you can use it if flying NW. Just take the bags with you on the train to the airport.</font>
??? The in-town check-in is inside the Airport Express train station, thus to get there, you have to have bought and used a ticket for the train. However, you don't have to take it, but you have to pay for it.
I don't know if NW participates (i.e. has a counter at the station), but many other airlines do. The only restriction is that if you are flying to the US non-stop, you have to check in at the airport. Thus, if you are going HKG-YVR-JFK in CX, you can still check in at the Airport Express station.