Xerte is well worth a look.
Xerte has been mentioned in other posts earlier in this topic, but it is worth noting that it has had further development since the post that compares it with eXe.
Xerte Online Toolkits offers a web server based authoring environment which uses templates to make page creation relatively simple whilst retaining the potential to create sophisticated content. This will support ldap authentication. I believe code is available to support authentication from within Moodle but I have not tried it. This will support collaborative content authoring.
For those who require greater flexibility then is offered by the Toolkits environment, Xerte is also available as a standalone application which enables content authoring at an object level, i.e. you add a page icon to your learning object and then add icons to the page. Icons come in different types including Text, Graphic, Drawing, Sound, Movie, Script, Interaction and Decision. Some of these can have their own elements added to them e.g. an Interaction can have a target area added for implementing drag and drop. Xerte is flash based so all icons inherit flash movie clip properties. Through the script icon you are able to programmatically control the other icons. The potential is incredible, though the learning curve can be challenging. It is noticeable that in the support List their appear to be a number of former Authorware users who are looking at Xerte as the development tool to use now that Authorware is no longer being supported.
If you want the on-line Toolkits ease of use in a stand alone product then you can select the Page Templates option from the Template menu in stand alone Xerte and you have pretty much the same authoring environment as offered by Xerte Online Toolkits. You can even combine the two because you can save sections of a Xerte learning object as a model and then use it in a Templates or Toolkits based project to add complexity that could not be implemented in the Template / Toolkit environment.
If you really get to know Xerte you can even create new templates to add to those available in Xerte On-line Toolkits or Xerte template based projects.
Xerte is well worth a look and the List based support is very responsive.
I hope this is helpful to you if you are looking for content authoring software.