Well, a lot has happened since my last post in this series...
First and foremost, SQL Server 2008 has shipped! It's great to have our geospatial database in production now, and you can download the RTM trial bits from http://www.microsoft.com/sql, or get the full Developer Edition from http://msdn.microsoft.com if you have an MSDN subscription.
Second, I had been experimenting with parsing Well Known Text representations of SQL Server 2008 spatial types in the mistaken belief that I wouldn't be able to use the geometry and geography types from within a client app (I had been misled by a response to a blog posting I saw back in the Feb CTP timeframe.)
This week, I had the pleasure of meeting with the geospatial team, and they set me straight. It turns out the geometery, geography, and the hierarchyid types are all available for client side use, and can be installed independent of the database server.
I'll explore the implications of this in the next few posts I do in this series, but in the meantime, you can download the MSI package which contains these types from http://www.microsoft.com/downloads/details.aspx?familyid=C6C3E9EF-BA29-4A43-8D69-A2BED18FE73C&displaylang=en - just scroll down to where it says "Microsoft SQL Server System CLR types" and click the link.