Originally Posted by London Dude

I agree, net net these changes are actually quite negative especially if you're Gold, and Silver to a lesser extent.

Don't be fooled by the marketing spiel in BA's announcement, this is essentially a transfer of wealth (in mileage terms) from high-value fliers to the majority of BAEC members who fly mostly in discounted economy.

Additionally, the changes regarding transatlantic redemptions, while adding more flights to certain routes, will result in a disproportionately larger number of AAdvantage members being added to the pool of award seekers. By a way of example (assuming very simplistically that AAdvantage's membership is 3 times the size of BAEC's):

pre AA/BA:
number of JFK-LHR daily flights: 8
number of fliers eligible for awards: 1 million (BAEC)

post AA/BA:
number of JFK-LHR daily flights: 14
number of fliers eligible for awards: 4 million (BAEC + AAdv.)

If you look at the average size of an AAdvantage account's balance, which given the relative ease of accruing AAdvantage miles I bet is far higher than your average BAEC account's balance, you can see why BA had to increase the mileage earning opportunities for BAEC members. If they hadn't done so, the weighting of AAdvantage members in the eligible redemption pool would have been much higher.

Overall, these changes result in a devaluation of existing BAEC miles for all current BAEC members. Frankly, in order to be fair what BA should do is change its "currency" to New BA Miles, and convert current balances in existing BAEC member accounts into New BA Miles at a rate of between 1:3 and 1:4, to take into account the large inflationary effect caused by both easier mileage earning opportunities and the addition of AAdvantage redemption seekers.