put my contact info in a public gist and say goodbye to me as a business partner.

Yeah, good point.

You can make the gist non-public by default (set public=false), and perhaps gists are the wrong tool, but something akin to gists seem like a good way to do something like this. I know Dave Winer was using the DropBox API in this way for some of his outlining tools.

But your point is well made, one of the downsides of the "web" as a platform is that it's hard to know what happens with the data you save to a random web application. I've had experience with product managers loading entire customer lists of emails into random "email validation tool"s, which were clearly just honeypots for foolish people's data.