StudioPress has introduced Simple URLs, a URL management plugin for WordPress.
The plugin was created as an alternative to the page redirects commonly used to mask links. Page redirects can’t be tracked and can cause permalink conflicts and performance issues. To get around these problems, Simple URLs uses a custom post type and custom permalink structure. Users can easily create custom short links on their own domains, manage those links and track the number of clicks each link gets.
The plugin is available for download from the WordPress plugin directory.
It’s essentially the same exact thing that GoCodes is, including the /go/ url portion
http://wordpress.org/extend/plugins/gocodes/
I’ve been using that for a long time now…