We are currently looking for an online html template editor for our community based software, allowing users to pick page templates from a library and then edit them online using a wizard/gui/editor. I have failed to find a commercial product that fits the requirements, but have noticed a few companies offering something that is close. The closest I have found is the template editor on http://www.mailchimp.com and this can be used as a baseline.
Basically, each template has the following attributes that can be customised;
Editable Text Areas
Editable Image Areas
Along with preview, save, etc.
We already have an existing system to display our templates, but it may need to be tweaked (by us) to get this working together.
The templates use some form of markup to identify the editable areas, example of how to do this are on the website.
This will be integrated into a new version of our own software which is written in c#/asp.net.
We will require constant updates and access to beta versions as much as possible.