We started the ETH ABI Working Group, which is aiming to standardize the ABI Interface Specification for Compilers, Web3 libraries, and other tools. If you are in one of these groups that consumes the ABI specification, please let me know so I can add you to this working group.
We also aim to create a standard test suite for ABI encoding/decoding that all of these groups can use to supplement their testing suite (and eventually merge all core featureset tests!).