I personally have been a great fan of Sql DMO for many years while managing hundreds of sql server boxes with a small team. It helped me a lot in audit and common maintenance tasks. With the introduction of Smo, Dmo became a deprecated feature in Sql2k5. With Sql2k8, MS has gone one step further and avoided installing Dmo automatically. However, if you still want to use Dmo for Sql2k8, you can download the feature pack from here -
http://www.microsoft.com/downloads/details.aspx?FamilyId=C6C3E9EF-BA29-4A43-8D69-A2BED18FE73C&displaylang=en. However, it would be nice to start using Smo and Powershell now.