cmb,
There is no forum module for EE yet. It’s on the to-do list, but not available yet. I never bother with Dreamweaver, but the ability to use it with EE is available in 1.1 which is in beta right now. There is a mailing list, but not the ability to automagically send out email digests.
RSS is available, and I have created templates that can be used to make html messages.
Using built in membership levels, you can collaberate on documents, but there isn’t an audit trail built into it.
There isn’t an ecommerce module out yet. It is also on the to-do list.
So in other words, some of what you want to accomplish is possible with EE, some is coming (no timetable) and some would be harder to accomplish.
The password scheme for EE is different than that used by InvisionBoard and PHPBB, but I did find a forum package that uses the same scheme, PunBB
Inside the Communicate section of the EE control panel, you can send out mail to member groups.
So do I think EE will meet your needs? It will meet some of them now, and some in the future.