There are several proposals for optimizing Bitcoin's scalability:
BIP100 - Periodically change the limit based on block size vote by miners
BIP101 - Increase to 8 MB on January 11, 2016, and double the limit every two years
BIP102 - Increase to 2 MB on November 11, 2015
BIP103 - Block size according to technological growth
BIP105 - Consensus based block size retargeting algorithm
BIP106 - Dynamically Controlled Bitcoin Block Size Max Cap
BIP8MB - Increase to 8 MB
BIPRosenfeld - Elastic block cap with rollover penalties
...
BIP100 - Periodically change the limit based on block size vote by miners
BIP101 - Increase to 8 MB on January 11, 2016, and double the limit every two years
BIP102 - Increase to 2 MB on November 11, 2015
BIP103 - Block size according to technological growth
BIP105 - Consensus based block size retargeting algorithm
BIP106 - Dynamically Controlled Bitcoin Block Size Max Cap
BIP8MB - Increase to 8 MB
BIPRosenfeld - Elastic block cap with rollover penalties
...
Bitcoin is a mathematical money system and voting isn't the way mathematicians achieve consensus.
There must be a better way to do this, like figuring out the definition of Bitcoin first and then seeing what proposals fit the idea of Bitcoin moving forward better than others.
The fact that 8MB option stands out (in the OP) by not having a link to the BIP (truth doesn't need a BIP) hints us at the correct solution.
