We've just done some testing on my brand new Blackberry Passport (a great QWERTY keyboard device but more on that in another review with our FV Player Pro.
Here's the device user agent is:
Mozilla/5.0 (BB10; Kbd) AppleWebKit/537.35+ (KHTML, like Gecko) Version/10.3.1.2576 Mobile Safari/537.35+
Here are some tests using my Blackberry Passport against FV Player, Flowplayer, JWplayer and video.js . Keep in mind that only the Blackberry Passport, Q10, Q5, Z10, Z30, Blackberry Classic, Blackberry Leap and P'9982 and P'9983 run Blackberry 10 OS. Any other Blackberries or RIM devices are running OS 7 or earlier and are not really capable of playing video at all.