Greg's proposal is to basically to flag a "-longterm" kernel once per calendar year. That long-term kernel is then maintained for a period of two years before it is dropped. The "normal" kernel releases will continue with their same flow and development cycle, which is dropping new point releases before a new major release occurs. These non-longterm kernels will continue to be what's used by most desktop Linux distributions and others. The -longterm kernels is what's targeted by enterprise Linux distributions (i.e. SUSE and Red Hat Enterprise Linux) for their long-term support model. The -longterm kernels will still have the same rules as normal kernel releases, with not introducing new features outside of the original merge window.
More details on Greg's long-term Linux kernel plans can be found via his blog. Greg will also be at LinuxCon 2011 this week.