I've worked with ivy on a project a few years ago and the integration with eclipse worked fine for the classpath and sources. I didn't check about the javadocs.

Ivy is mainly a tool to work with ant, so it makes some sense that IDE integration is not in the same project, but as far as I could see, ivy and the eclipse plugin are written by the same people.

The eclipse plugin was actually one of the reasons for choosing ivy over maven, because at the time maven was moving to 2.0 and its eclipse plugin was not yet available or stable. The other reason was the documentation. At the time there seemed to be more documentation about ivy than about all functionalities of maven together.