On May 11th, we released Miro 4.0 rc1. It has some known issues, but we've fixed a ton of stuff since the beta. I encourage you to upgrade to rc1 and let us know if you run into any issues.
Specifically, we need your help to test:
using Miro to sync media between Miro and your Android device
using Miro to stream through DAAP to other DAAP clients on your network
Miro on Windows
Builds are located on the nightlies page in the Sticky Files section.
Note that this is not a final release release! There are still some problems and tweaks we're working on.
Also, we really need help with translations. If you know multiple languages, please help us translate. On Launchpad, there's a Miro section for translations.
Also, if you help with testing and translation, please let me know so I can gleefully add you to the credits where you rightfully belong!