I don’t see too much distinction between these aside from that User Research may be more tight in scope and specific than Market Research. That being said, I think both are valuable to designers, and I often provide both aspects to clients in various forms.
If anything I think Market Research, is almost more valuable to a project as it defines the starting point, strategy and opportunity. It should be the foundation of any project, design brief or concept, no matter if done by Marketing or Design.
Maybe I’ve yet to work with a strong marketing department, but I typically find most marketing studies and marketing people (like sales) are too often focused on the past (what has been done), vs. the future (what could be done). In this way I believe that a proper strategic approach to design is key upfront to identify opportunity, and that most focus groups, “marketing reports” and the like are pretty much useless.
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