We use Chef at work, and while there is a rich repository of
cookbooks, I never used for them anything but inspiration for
writing our own. Usually the recipes contain code specific to
someone's environment, or is not sufficiently configuration
driven to suit our needs.
Btw, Chef comes in two flavors, we prefer the server-less
version, chef-solo, and it is not have feature parity the
"regular" chef agent (bags, search etc) which further fragments
cookbooks.
While community playbooks sounds great when you look at these
things, in practice, I think Michael is exactly right.
/Allan