We ended up building Mac and Windows apps for http://www.webhook.com built on a Node / Chromium shells. Essentially we're a Wordpress competitor, but Node powered, and wanted to provide a simple one-click install for people that didn't know how to work their command line or how to install Node properly. This solution ended up working great. It basically allowed us to build a non-destructive sandbox dev environment for them that had a UI experience similar to the CMS itself. Better yet, the app points to hosted JS and CSS files so really there's never a need to "update" the app. When we have feature or bug changes, we just push out new files and everything just works.
This kind of stuff isn't for all apps, but for our use case it was almost too good to be true. We built everything out in about two to three weeks. I don't know how long it would have taken for us to do something similar with true Desktop tooling.
Here's a video of the end result in case anyone in interested...