I just used it with some friends for the first time today. I’ve never heard of it before. It works in the browser! Group video chat with tools!
Very fast feature overview based on my current experience: Video optional. Audio: a button to join just with listening, or to join with microphone access. Whiteboard! Public chat! Notes, that are different from the public chatroom, editable by everyone and with basic wysiwyg formatting! You do not have accounts, you just type your name. You can set your “status” to confused, happy, sad, applauding, a few others. Audio and video are clearer in this group than with meet.jitsi with the current people. I was able to join with video and listening audio on my phone (using mobile safari), but not microphone (might’ve been an issue with my earphone). I then switched to laptop.
Here are two organizations offering hosting service for BigBlueButton.