I don't mean to sound like a broken record, but we had "Symphony" training yesterday. This basically involved just transferring our preferences from Unicorn to Symphony. Everything else is about the same. BUT, I learned that Web Reporter, which previously was just for the Cool Kids who used Horizon, is now available for Symphony (Unicorn), too. Other than that, I didn't see a lot of Horizon in the key enhancements.
We were asked to play with Symphony, pretending to do our jobs as if we were using Unicorn Java Workflows. So I did. Was there anything at all that was different? Nope. All steps, prompts, and menus were pretty much the same. I believe it will even still ask me if the "diskette is ready" when I go to import something.