First of all, I've looked over the program comparison chart that is linked from this forum. It didn't really answer my question that well, so I thought that I would try asking here.

At the moment, I am living in the US. But, if all goes according to plan, I will be living and working in Japan.

I will be flying UA in a few weeks, and I was wondering whether I should join their program (since they will likely see more of my $$$ in the short term) or NH's program, since they will get more of my money in the long term and I would (hopefully) have enough miles by then to get some free tickets.

Thanks!