I've been pondering this a little, but I'm not sure where it belongs. It's in my blog backlog, though, so here it lives. I worked in advertising for a short while and noticed some fun quirks of the industry. ("Worked" in the industry? Hah! Actually, I was answering phones.)
You see, executives had a rolodex on their desk, that they protected like a vital organ. And it *was* a vital organ -- the contacts in there were "theirs," and made the executive uniquely valuable. When an executive quit, or was fired, the first thing they did was grab their rolodex. Only then would they make sure they had trivialities such as car keys or their wallet.
Sysadmins have an analogue ... our wiki pages. But they're typically hosted on an internal company server, readable by the rest of the team. And then, some sysadmins refuse to post information to the wiki, guarding it like their "rolodex." They don't say as much, but you know which ones are trying to stay valuable by not spreading tribal knowledge.
How similar are these? Sysadmins and ad-people have mostly opposite attitudes towards the information that makes them valuable, but the analogy itself might hold water. Has there been a change in the advertising field, as companies have moved to shared, server-based customer relationship systems that the corporation owns? I wouldn't dream of hoarding my information, and I think *that* makes me uniquely valuable ... so am I "right" or just used to having the corporation "own" my information? I wonder.