Enable on user-by-user basis?

I run a multiuser blog with many guest bloggers who depend on the visual editor. Some of us would like to use this plugin, but we’d like it disabled by default for the rest of the users and for new users. Is there anyway to enable this plugin for only some users of the blog? Or might this be added as a feature request?

http://wordpress.org/extend/plugins/markdown-on-save-improved/