Mozilla have WebRTC-bases Hello video chat service plus including support for MP4 video on OS X.
Just like before, you can start these plugin-free video chats by sharing an automatically generated link with whoever you want to talk to or by using the contacts from your Firefox account to start calls. Before, you had to sit and wait for your contact to join the room. Your contacts can be on Firefox, Chrome or Opera. Now, a small window with a self-view pops up and you can continue to surf the Web until your contact joins the call. It’s a small but welcome change for those who regularly use Firefox Hello.