Microsoft have officially announced their intention to have Katmai available in 2008. (The title of this post is nothing more than idle speculation. Katmai doesn't have an official name yet.)
http://www.microsoft.com/presspass/press/2007/may07/05-09KatmaiPR.mspx
Among the features announced are the Declarative Management Framework, the Resource Governor and also support for geographical data, documents and images in the database.
Declarative management will allow you to manage your SQL Server configuration across many databases and servers by defining policy rules that are automatically applied, montiored and enforced. It's a great feature for large data centres and complex environments. It's also unlike anything I have seen from the other DBMS vendors.
The Resource Governor is a very welcome and overdue improvement. It means that for the first time you will be able to allocate and limit SQL Server resources to support individual workloads with different priorities and needs running concurrently on the same server. That's going to help deliver more consistent performance and availability from every SQL Server instance - for example by making sure that ad-hoc decision support queries can't impact your operational systems by starving them of resources.
The new data type support is potentially exciting too. I've been asked more than a few times about support for spatial data within SQL Server. It's something that DB2 and Oracle already offer.
You can read more at:
http://www.microsoft.com/sql/prodinfo/futureversion/default.mspx
And more here as more information becomes available...