Good point. I think the first decision someone needs to make in this case is whether they want their content type and fields to depend on CCK being present. It's possible either way, of course, but a whole lot more work.

Victor wrote:

One way to avoid this whole problem would be to adopt an everything in code process (either through features or leaning heavily on the installation api module and bulk export modules).

That way, updates are all like module updates.

See http://nuvole.org/blog/2010/aug/24/features-based-development-workflow

The technique works whether you use features or not.