There is a discussion about two different Bitcoin Improvement Proposals - BIP 12 and BIP 16, and probably only one of them is going to be included in Bitcoin 0.6 (miners will decided which by a majority vote of mining power).

Can anyone summarize the core differences between the two proposals, and their respective advantages / disadvantages?

There is a discussion about two different Bitcoin Improvement Proposals - BIP 12 and BIP 16, and probably only one of them is going to be included in Bitcoin 0.6 (miners will decided which by a majority vote of mining power). LukeJr proposed an alternative to BIP 16 called OP_CODEHASHCHECK.

Can anyone summarize the core differences between the three proposals, and their respective advantages / disadvantages?