Sebastian,
recently someone recommended Ivy to me because he saw that we were hosting our project dependencies in our Subversion repository.
When I see axis.jar in a VCS system, I always ask the question: "do you know which version it is?". If you're serious about managing the 3rd party libraries, you should be able to answer the question precisely.
You want to upgrade a library from 1.0 to 2.0: how do you remove all transitive dependencies from the 1.0 version? This may not be an issue if you have 3-4 jars to manage, but our application has about 100 direct and indirect dependencies.
You want to test a new version of that library first: you can to it by changing just one line in the ivy.xml file and test locally. The upgrade doesn't work: just revert your single change.
However I see a major disadvantage over dependencies in a VCS repository: If a project is dormant for a longer period of time an artifact (i.e. a library) may longer be available (in a certain, required version or the repository may not exist anymore).
If you download all your dependencies from a Maven repository (check the ivyroundup project on googlecode) you are immune to that problem (as long as the library is available on that repo; but it's Maven's point).
Hope this help -Vladimir
