Canon USA has just published a YouTube video entitled, "Committed to World Class Service & Support." Yes, it's a self-serving marketing video – but from our experience, Canon's Customer Service is very good.
In the times I've had to call in, I've always gotten a friendly, knowledgeable and caring person on the other end of the line. As stated in the video (and from our own personal experience), Canon tends to stand behind their products. [Sean]
From Canon USA's YouTube Channel:
Take a behind the scenes journey with the Service & Support team at Canon. Visit our 100% US-based call center staffed with all Canon employees and get to know our factory trained service technicians. Learn why the satisfaction of our customers is our first priority.