They spell it out, but it's still very unclear - the first sentences distinctly says that no passport without a "biometric chip identifier" will be acceptable for visa free travel after October 26th. Then the fourth sentence says that, if you have an existing UK passports issued before that date which doesn't have such a chip, you will still be able to travel without a visa, until that passport expires.

They can't both be true. Have US customs been told to ignore the law for UK passport holders, but not so far as anyone else is concerned? Are they making this up on the hoof?