I have attended a few sessions this year at uSwitch. Sessions are based on suggested topics/problems those in attendance would like to work on. A vote is taken, and we then break out into groups and work on the topics/problems. A brief demo is shown to the group at the end, and we finish shortly after 9pm. I have not attended a Thoughtworks session yet, but I suspect they follow a similar format.

Thanks for the reply.

Hey, I can confirm the Thoughtworks dojo follows the same format

Sorry I can't come tonight but I will make an effort next time.