I recently made the jump to JBuilder 2007. As a long time user of JBuilder (I started using JBuilder back with version 3) I have to start off saying that this version is quite a bit different from any other JBuilder. If you are an Eclipse user you will be quite comfortable with v2007, otherwise there is a hefty learning curve.
At the moment, I am actually having trouble with the registration process, so I have not yet tried out the borland specific features, I am just getting familiar with the Eclipse 3.2 functionality.
One thing I noticed right away is that I find the UI designer a big letdown from the old JBuilder.
I will post more here in a bit when I get further along in the process.