Question: I'm looking mainly at things like new SQL syntax, new kinds of locking, new capabilities etc. Not so much in the surrounding services like data warehousing and reports...

Answer: 
Did you check the whitepaper on the website? 
 [SQL Server 2008 Overview.](http://www.microsoft.com/sqlserver/2008/en/us/overview.aspx) 

I cannot recall off the top of my head, but it atleast has a nice database to object linking functionality. They have geospatial types too, if you need to use those.
HotAdd CPU. <http://msdn.microsoft.com/en-us/library/bb964703.aspx>