+ Changed the URL pattern for accessing wicket from "/app" to "/"
BEFORE: http://localhost:8080/MyNiceApp/app
NOW: http://localhost:8080/MyNiceApp

Implication: This means you cannot access the "Grails Views" anymore. Wicket is the default UI with this change
You can change this obviously by reverting this change in your copy of the grails-wicket code.(just revert the changes in this commit)

I did this so I can make the app be accessible at www.myniceapp.com instead of www.myniceapp.com/MyNiceApp/app
Alternative is to use Proxy directives in Apache with which I had limited success

See this blog post for how I got www.myniceapp.com to work:
http://grailslog.wordpress.com/2013/09/02/the-most-important-grails-tip-of-all-deploying-an-app-to-the-root-context/