I'm not sure that would really be very appropriate. They've already voiced their disappointment at the sentence - I don't think they need to be contacted by strangers to press them on the matter right now.
The point, surely, is a more general one. Driving without due care and attention resulting in the death of an individual is treated less seriously than manslaughter - though the effect is the same. IANAL - But gross negligence is the test for manslaughter. ALL road users have a duty of care on the road, and this duty was breached causing the death of an individual. Drivers in particular have to be well trained to use their vehicles, so it can be demonstrated that causing death is negligent... but for some reason juries didn't convict people for that, and so causing death by dangerous driving was introduced.
Even though the effect is the same, it is treated as a somewhat lesser crime and the guilty are often given a light tap on the backside and told not to do it again.
This happens time and
again and we all should be disgusted by it - not only as cyclists but as other road users as well be it cyclist, driver, rider or pedestrian. However (and this is
Good News) Hull MP Karl Turner
has asked David Cameron to impose tougher sentences on dangerous drivers. I would urge people to contact their MP to ask them to support this.