We talk a lot about Web service versioning (and Don Smith is working on what should be an excellent article on the subject for MSDN), but then there is the issue with assembly versioning.

Hervey Wilson, the development manager for WSE, talks about the unique challenges of versioning WSE assemblies.  In particular, WSE 2.0 will not have wire-level compatability with WSE 1.0 so the solution is to throw a “2“ on the end of the assembly name.

This seems to be an excellent solution if you consider the fact that if you have an application that needs to talk to a WSE 1.0 Web service and a WSE 2.0 Web service at the same time, you will now be able to make that happen.