Thanks for your interest in our award-winning enterprise wiki, Confluence. Sorry for the delay in responding, but we released Confluence 2.9 today and I wanted to wait and reply after the release because some of the new features may be very appealing to you. Based on your requirements, I think that Confluence could be a very good fit for your law firm.Email notifications of the changes
Yes, highlighting or only showing the changes to the page itself;
Yes, Confluence allows users to 'watch' pages (or entire spaces) and then sends you an e-mail every time they are updated. The e-mails themselves contain the page and a link to the page where you can easily view the most recent changes. The changes are presented in a nice format highlighting both what has been deleted and what has been added.
Here is a quick overview: http://confluence.atlassian.com/x/oCAC
Confluence also allows the creation of custom RSS feeds that allow users to subscribe to certain pages, spaces and blogs and lets them check the updates at their discretion without filling up their inboxes.
Checkout on editing
Confluence has very strong capabilities in this area. If a user clicks to edit a page that is concurrently being edited by another user, they will be notified. Confluence can automatically merge their changes if the two users edit different parts of the page. If there are any conflicts, Confluence will display them for you and give you the option to either 'Overwrite' the other user's changes, 'Merge your changes' manually, or 'Discard' them.
Our page describing this functionality is here:http://confluence.atlassian.com/x/TzUC
Confluence also has very fine grained permissioning, meaning that you can easily restrict which individuals and groups can view or edit a page.
Integration with Sharepoint / MOSS 2007.
Microsoft is embracing partners who are leaders in Web 2.0 technologies and so we had SharePoint Connector designed. This plugin allows for integration between Confluence and SharePoint on multiple levels. You can embed SharePoint content on a Confluence page, create links between the different programs, run searches among content on both programs and more.
You can see the homepage for the connector here:http://www.atlassian.com/sharepoint/default.jsp The documentation for the SharePoint Connector offers more comprehensive information on the product: http://confluence.atlassian.com/x/9AHrBQ
Today, we also release a free plugin called the Office Connector. This makes it easy to convert MS Word documents into Confluence pages and also to embed Excel and PowerPoint content. I'd highly recommend watching the video on its homepage: http://www.atlassian.com/office/
Has your law firm tried an evaluation of Confluence yet? You can download a free 30-day evaluation and see how it works from: http://www.atlassian.com/software/confluence/ConfluenceDownloadCenter.jspa
It sounds like they are addressing the holes we have found in SharePoint wikis.