Caterpillar

Even if, for day-to-day operations, Caterpillar adopted a continuous deployment model in favor of discrete releases, having those discrete releases would still be worthwhile. I already mentioned the communication and marketing benefits. But also, some users might just prefer a slower pace.

For users who are not familiar or comfortable with a continuous deployment model, knowing there's a release, let's say once a year or so, stable and officially blessed by the project, might have a calming effect. And if you are reviving a project you haven't touched in a while, it would be good to have a series of stable targets to use as milestones in your upgrade path.

I'd even be totally happy to maintain and support those releases for an extended period, as a paid service. But that would be far in the future. Let's worry about the initial user first, before making too many plans about the well-paying ones.