I think Debian's long release cycles don't make much sense in this day and age. To me, a rolling release model makes much more sense, especially in this world where security updates are being done constantly, and are generally focused on the more modern branches.

For enterprises where software is part of the core business, keeping up with updates on a regular basis is probably better than doing large upgrades every once in a while (for one thing, tracking down regressions is a lot easier when you don't have to search the entire haystack).