Yes. Ultimately, it's a distinction that would be interpreted by the courts, but I would argue that there are certain classes that clearly fall in each.
Non-commercial infringement would be the private copying that Canadians do every day with their content: making backups that right now aren't covered by exceptions under the act, and moving content off a CD onto an iPod, for example, again an activity not covered by an act. Those are all private, they're plainly non-commercial, and they also plainly don't undermine business models. In fact, because they make content more useful, they actually provide incentives to purchase the content in the first place.
The commercial-scale infringement is different: you're entering into a field of commerce and either trading on it or using content in such a way as to make money in some other peripheral way. Where the distinction gets very difficult and where we have to engage in a line-drawing exercise is that somebody might have a website that has something like Google ads, which pay a very small amount and help to cover the cost of the site, of the blog, or whatever it is. Those are the cases where I think you have to be careful about saying when something is commercial and when something is simply trying to make it more remunerative to engage in a hobby.