Inspired by my petty shot at making SQL Server spatial, Ricardo Stuven has been working the new CLR in SQL Server 2005 and started adding almost all basic spatial functions, and implemented some aggregates, stored procedures and table-valued functions in SQL Server. He even started an Open Source project where you can check it out (yet another open source .NET GIS project we can add to the .NET tribe... ;-))
Read his comments on his approach, including query examples and a list of features which he posted in an update on the SharpMap forum today.