Sanyo just released a new Eneloop low-self-discharge battery called "XX powered by eneloop AA", providing more power with 2500 mAh.
More information on Sanyo Website: here
I use Eneloop batteries for few years now and I'm quite happy with them. Going to 2500 mAh will give even more flying time !
Price is about 19 Euros for 4 cells, compared to the 15 Euros for the standard 2000 mAh we already know.