If the driver pleads guilty-you will be able to use that against him as an admission of negligence during your civil cause of action.
If the driver pleads not guilty and is found to be guilty after the trial, you will have a harder time using that against him since there is no admission against interest to be used against him. In many jurisdictions you won't even be able to mention the citation even if there is a finding of guilty.
I hope this helps-
Disclaimer: I am a lawyer licensed in the State of Illinois only, and I am not your lawyer (unless you have been in my office and signed a contract). This communication is not intended as legal advice, and no attorney client relationship results. Please consult your own attorney for legal advice. This is for informational purposes only.
It would help to testify in court against the other driver. If the judge finds the other driver guilty it may convince the insurance adjuster to go ahead and pay for your car repairs and any other damages. Also, if the damages are significant you may want to have a court reporter take down what the other driver says in traffic court. This evidence could be used in other legal proceedings.