The CyanogenMod team explained that while Exynos 4-based devices won’t get the general release CyanogenMod 10.1 version for the time being, they will still have access to nightly builds.
The “affected” devices include the Galaxy S2 (AT&T and international versions), Galaxy S3 (international version), Galaxy Note (international version), Galaxy Note 2 (AT&T, T-Mobile, international GSM and LTE versions) and Galaxy Note 10.1 (Wi-Fi and international versions).
Nightly builds will continue to roll out, so users will continue to receive “the latest bug fixes, security fixes and features,” but bug reports will apparently not be accepted. The team is not yet ready to offer a general release CyanogenMod 10.1 version to Exynos 4 devices, because there are plenty of issues still left to resolve, according to its recent Google+ post:
That said, to those keeping an eye out for a CM 10.1 general release for Exynos 4 devices, there won’t be one. Supporting this family of devices beyond CM 9.1 (ICS) has proven difficult to accomplish, with various issues surfacing from the binaries and sources we have to work with.
However, we are not going to be giving up on this platform, especially given that the i9100 and i9300 are in the top 3 of our user base (according tostats.cyanogenmod.org); we know many of you are counting on us for support. Our maintainers thus far have done an admirable job getting these devices to work well in their current nightly form. There are still plenty of issues left to be resolved, and they aren’t the type of issues that will be solved in days or weeks. It is because of those issues that a general release has been withheld.
The team mentioned that Exynos 3 and Exynos 5 devices will continue to be supported, and that it it’s also working to bring the Exynos 5 Octa platform “up to release quality.”