Theres no excuse for what the bus driver did and I have only seen the footage of a couple of seconds before the incident, im not sure if you have noticed at one point the cyclist has his bike leaning across the front of the bus to stop it from moving off before swerving across in front of the bus to hinder its progress.....in my eyes that is pure provocation on the part of the cyclist.
If there had been a previous incident with the bus (pulling out without indicating etc) both parties should have been adult enough to get over it.
There seems to be a real holier than though attitude by commuting cyclists these days who expect everyone else to abide by every road law but are completely happy to jump red lights, not signal to indicate their intention, ride down one way streets the opposite way etc.
You just need to have a look at some of the helmet cam videos on youtube of the despicable behaviour of some of these guys.
Before you accuse me of being anti cyclist, I have been cycling all my life and currently own 3 bikes which I use often.
In fact on a recent visit to London, my wife and I were riding through Hyde park on our Bromptons (which just happened to be about 5pm) and the attitude of a fair share of the 'serious' cyclists towards us getting in their way as they tried to shave a quarter of a second off their journey home was terrible.
The Bus driver in the above incident was way out of order but you can understand the frustrations of vehicle drivers towards cyclists too!
Heres an interesting bike v bus clip........
Cyclist in London, nearly gets himself killed. - YouTube
Decide who was at fault here