This includes the fix for HTTP headers being lowercase - please see https://github.com/artfulrobot/uk.artfulrobot.civicrm.gocardless/issues/71
It also includes changes to the way contributions are completed/repeated, using newer APIs. See change log in the README, and specifically https://github.com/artfulrobot/uk.artfulrobot.civicrm.gocardless/issues/63
I will release this as non-beta once I've heard back from GoCardless on a couple of things, but that's me being super cautious - all should be fine.
Remember to download one of the following and NOT The source code
1.9.2beta2 includes a fix for the upgrader that was present in the 1.9.2.beta release