Be sure to back up any important data, and if possible clone your hard drive before applying the update. If you have any issues post-update, boot using UniBeast or rBoot.
What we know about 10.7.3 so far...

- 11.3.0 Darwin kernel
- Improved AMD, Intel, and NVIDIA graphics drivers.
- If you use customized or edited graphics kexts, it will be necessary to make the edits again using   the new drivers as a base.
- The update will replace your AppleHDA.kext.
- If you use ALC8xxHDA for onboard audio, you will have to reinstall AppleHDA Rollback using MultiBeast before rebooting.
- If you use toleda's new AppleHDA for onboard audio, you will need to reinstall it before rebooting.
- If you use VoodooHDA, you will not need to make any modifications.
- If you use Sleepenabler.kext, remove before updating.

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