An Obsidian forum post explains how Pillars of Eternity players can choose to opt-in for beta patches for the just-release RPG, appropriate for those willing to live with some bugs in their bug fixes (thanks nin). Word is: "We will make a formal announcement to the community when we are going to put the latest patch up for beta testing. We are starting this process with the 1.04 patch." Here are some caveats:

• Right now we are only running this beta on Steam. The reason is that Steam provides a simple way to get folks into the beta. If any players know of any games that ran betas on GOG, please let me know so I can investigate.
• These patches may be unstable. We will be doing work on the patches and they haven't gone through a full QA cycle so unexpected things can happen. To be safe, I would avoid using any saved games that you do not want to get corrupted. If you do want to use those saved games, it is at your own risk.
• These patches may stay the same over the entire testing period, but that is unlikely. There might be frequent build changes, so expect to have to download multiple builds over a testing period.