One of the more radical departures that Sakai 3 makes from traditional LMS design is that everything in the system is treated as content. A traditional LMS is an aggregation of tools—discussion boards, grade books, test engines, wikis, assignment drop boxes, etc.—each of which has its own data model in a relational database. It’s really a hodgepodge of separately designed tools that are knitted together through a user interface layer and a few common services. In contrast, Sakai 3 is being built on top of the Apache Jackrabbit reference implementation of the Java Content Repository (JCR) standard. Everything is treated as content, including grades, test questions and answers, discussion threads, syllabi, personal profiles, chat messages, and so on.
This approach has some benefits in terms of shoring up common weaknesses in LMS designs. But, more profoundly, it also leads to some pretty fundamental changes in the way that learning environments can work, thanks in large part to the strong and growing adoption and maturation of useful content integration standards.