Thanks to Johnson for giving me a good term to Google with (sans ridiculous false positives).
Here is a list of "feature tour" solutions I've found:
- Joyride | http://zurb.com/playground/jquery-joyride-feature-tour-plugin
- Intro.js | http://usablica.github.io/intro.js/
- Hopscotch | http://linkedin.github.io/hopscotch/
- Crumble | http://blog.tommoor.com/crumble/
- Pageguide | http://tracelytics.github.io/pageguide/
- Bootstro.js | http://clu3.github.io/bootstro.js/
I'm sure there are more out there. These solutions can make it far easier for a developer to implement better feature introductions to users.