You can read what our product marketing folks have to say about it here.
If you look around your desktop, there are many sets of "information organization structures" (IOS) --- collections of taxonomies or webs of information. Examples include:
There is clearly a lot of wasted effort. It is actually much worse than just wasted effort. Its organization of information based on the protocol used to access it, not based on what its about or where the user wants to put it. This balkanization is at the root of many of our information problems.
NavCenter is an attempt at solving some of these problems. In particular, it provides a way of navigating all of the above sources of data. Furthermore it allows you to integrate all of them. E.g., you can create a workspace called Sailing under which you have some local file system folders, portions of Yahoo!, Excite, some live search queries, ... So, its a lot more than simply slapping a common UI over multiple distinct sources of data.
NavCenter also makes it very easy to manifest new data sources into NavCenter without any changes to the FE code. The FE widget only talks RDF. Everything, right from the structure of the tree, the columns that should be presented, the menu commands for each item, ... comes from the RDF graph. We hope to make all aspects of NavCenter both scriptable and declaratively specifiable.
Please do not judge NavCenter by what it is today. It is very much work in progress. We hope you will help us make it better.