At least for the people who send me mail about a new language that they're designing, the general advice is: do it to learn about how to write a compiler.
When I read commentary about suggestions for where C should go, I often think back and give thanks that it wasn't developed under the advice of a worldwide crowd.
C is peculiar in a lot of ways, but it, like many other successful things, has a certain unity of approach that stems from development in a small group.
I can't recall any difficulty in making the C language definition completely open - any discussion on the matter tended to mention languages whose inventors tried to keep tight control, and consequent ill fate.
C was already implemented on several quite different machines and OSs, Unix was already being distributed on the PDP-11, but the portability of the whole system was new.
At the same time, much of it seems to have to do with recreating things we or others had already done; it seems rather derivative intellectually; is there a dearth of really new ideas?
My work was fairly theoretical. It was in recursive function theory. And in particular, hierarchies of functions in terms of computational complexity. I got involved in real computers and programming mainly by being - well, I was interested even as I came to graduate school.
A new release of Plan 9 happened in June, and at about the same time a new release of the Inferno system, which began here, was announced by Vita Nuova.
One of the obvious things that went wrong with Multics as a commercial success was just that it was sort of over-engineered in a sense. There was just too much in it.
The visible things that have come from the group have been the Plan 9 system and Inferno, but I hasten to say that the ideas and the work have come from colleagues.