Unless it's a security issue a huge usability issue, I'd suggest next release. (Not point release.) But it's up to you.
I think with the hugepages settings debacle its better to get this out as soon as possible. Most users won’t be visiting the forums to find what went wrong, they’ll just think the KVM version is broken and move away.
I thought of an elegant solution but I don’t want to complicate things. What if whonicheck uses virt-what to determine what hypervisor its on and accordingly decides to show a new bulletin with the releavnt link to the changelog section - only for the hypervisor it is on?