MS is now leveraging their products to use more .NET and SQL Server 2005. E.g. team foundation server (new source safe from MS) stores everything in SQL Server 2005. They are also building a new OS from scratch code name 'Singularity' (http://www.microsoft-watch.com/article2/0,1995,1882174,00.asp?kc=MWRSS02129TX1K...) and they are writing it using C# and Sing# (a derivative of C#)
Yesterday I installed SQL Server 2005 on my machine and found its great. We can install both SQL Server 2000 and SQL Server 2005 on the same machine and SQL Server 2005 can be used as a client to connect to SQL Server 2000 database. Also we can restore a SQL Server 2000 backup into the SQL Server 2005 database which is great for migration.