I was recently working for a client of mine and I needed to migrate him from his old installation of Simple:Press to the much superior bbPress.
I had a look around for the answer and it wasn’t tremendously obvious, and there was no available plugin for the task. However, I did come across an unpublished plugin which professed to do the trick.
So, after taking a backup, I proceeded to give it a go. After creating a plugin from the code and activating it, I ran the plugin by adding a query var to the website address, like so:
Once I did this, the plugin swiftly imported all of the forums, threads and posts successfully. One thing wasn’t right though: bbPress’ statistics weren’t totalling up correctly. However, this was easily rectified by going to Tools > Forums and using all of the tools to repair and recount the forums.
A very fast and painless transition, despite the initial apparent lack of information on the subject.