Nick, I'm wading throught the addition of workflow, so if you'd like to do Tasks, please go ahead. Could you post the preliminary data model before doing too much work on it, though? It would be nice to discuss it before we commit too much to a particular data model.
The Gantt and other views will be fun to develop I think, but should probably come after we've developed some of the other portions a bit.
I looked briefly at your work on the addition of the content repository. It looks good (although I don't really know very much about using the CR yet).
I'll continue working on workflow this week, and keep you all informed.