Chinese mining pools seem to have played the decisive role in the debate. As CoinFox wrote recently, a joint statement of BTCChina, Huobi, F2Pool, BW and Antpool favoured a compromise an increase of the block size to 8MB instead of 20MB.
Chinas five largest mining pools gathered at the National Conference Center in Beijing to hold a technical discussion about the ramifications of increasing the max block size on the Bitcoin network. ....
The bitcoin miners of China agree that the blocksize must be increased, but we believe that increasing to 8MB first is the most reasonable course of action. We believe that 20MB blocks will cause a high orphan rate for miners, leading to hard forks down the road. If the bitcoin community can come to a consensus to upgrade to 8MB blocks first, we believe that this lays a strong foundation for future discussions around the block size. At present, Chinas five largest mining pools account for more than 60% of the network hashrate.
The long debate over the bitcoin block size is over. The updates being done to the bitcoin code have been published by the core developer Gavin Andresen on GitHub. The block size will change from 1MB to 8MB, with further doubling every two years so in 2018, it will reach 16 MB, then 32MB in 2020 and so on.
2016: 8 MB
2018: 16 MB
2020: 32 MB
2022: 64 MB
2024: 128 MB
....
finally. a good and conservativ approach.