People don’t buy plumbing, they buy a nice house that happens to include plumbing (otherwise it wouldn’t be a nice house).
So if OpenID and all the other members of the “Open Stack” are mere plumbing, as I have come to believe, they are the plumbing of what? What is the equivalent of the house here, i.e. the thing that people buy or want?
It could be the plumbing of the internet. Like HTTP, TCP/IP, DNS and so forth. But I think that misses the picture: stovepipe sites work just fine on the internet without these new technologies.
It could be the plumbing of what some people now call the “social web”. Perhaps, but I have to admit I have a hard time believing that anybody will go out and want to acquire “the social web” like they would acquire a house. It’s even easier to say “I’m going to get an OpenID today” than it is to say “I’m going to get the social web today”.
I think that “what” is the big elephant that has been in the room since the very first identity discussion that I participated in so many years ago.
That is what we need to figure out, as a budding industry, more than anything. Plumbers have no business, and plumbing supply stores have no customers, unless there are houses and people want to buy them.
I do have some opinions … some other day.