Looking at this from a civil liability, insurance perspective, the driver is at fault. I am sure the SUV's insurance carrier will set reserves at the policy limits and probably settle this claim ASAP. I think many here are looking at this from a self defense perspective and may be influenced by the stereotypical "out law biker" image portrayed by some motorcycle gangs and the media. Gloria Allred likes to take high profile cases, but I doubt she would take a case she was not reasonably confident of winning. I also doubt this will even get to court, the insurance company will make an offer, probably for the policy limits and Allred will take up to the customary 33% and it will be settled.
Now as far as criminal charges against the driver, it appears that the prosecutor is not charging the driver. That's his discretion, he may feel the drivers actions were in fact self defense or due to the overwhelming popular support the driver has, he may feel he couldn't get a conviction if he does bring this to trial.