"Would the real Slim Shady please stand up?"
We want multiple 'kik's and multiple Shady's simultaneously. So record the gpg sig of the author in package.json, and filter the name + semver against just their published modules when updating.
Depending on how unique you need to be:
npm install <module> --save
npm install <author>/<module> --save
npm install <gpg>/<module> --save
On a side note, npm-search really sucks. It lacks a lot of fine-grained filtering. I'd love to be able to search by tags, or exclude results with an incompatible license, or even prioritize results by specified dependencies. npm-search needs love.