CyanogenMod 9 hits stable release and now you can update OTA.
"The modding community has given Android enthusiasts another reason for them to enjoy modding their smartphones. If you liked the concept of Over The Air (OTA) updates when using the official Android version from the manufacturer, you can now get OTA updates for custom ROMs as well, like CyanogenMod 9 for instance. This will surely ease the “pain” of manual updates, especially when new builds, like nightly ones, come frequently enough to be able to want to speed up the process."
So I read this article about the new CM9 stable, and how you can update it OTA. But I'm skeptical to try it.
It links to this website:
Which apparently lets you update it without having to do it manually.