This kind of slipped through the cracks
Harmonix Music Systems (the creators of "Rockband" and "Dance Central") used Bullet for collision detection and simulation in "Fantasia: Music Evolved" (for the XBox360 and XB1)!
You can check out the game here:
http://www.harmonixmusic.com/games/disn ... c-evolved/
... and check out the IGN review video here:
https://www.youtube.com/watch?v=UyLwPIXhX-o
I was the programmer that was tasked with integrating Bullet into our internally developed engine and editor. Except for some minor issues, the experience was very pleasant. Having access to the source code was definitely a plus!
A big thank you to the team that developed and contributed to the Bullet project!