I have had the opportunity to work with the new Pipes capabilities in Autodesk Civil 3D 2006, and I have been both pleased with what it can do, and surprised by it's ease of use.
The interface for creating pipes is very similar to how we create alignments and profiles already. This makes adopting the new capability very easy.
The concepts already learned for managing and using styles easily apply to pipes and structures.
More glipses to come.