I have been flying BA for the last two years but got tired of their misterly ways with the type of tickets my company buys - 0 tier points and 25% of miles flown on offshore fares.

I am now switching to AF/KLM and already have miles on FB and OnePass both recently and also from the past. What I need some advice on is which program I should collect miles on in the future. Note that I live overseas and am travelling to the US quite a bit but will also be travelling within Europe. I will mostly be flying out of AMS - is it better to collect all miles on OnePass or FB whether I fly KLM or Continental? Which has better upgrade possibilities? Are the programs such that it doesn't matter which I use as the benefits crossover to the other airlines equally?

Finally, does any know if I can collect miles on Air Astana?